Tire Care
& Safety
Pressure
Tread Depth
Rotation
1
BASIC TIRE INFORMATION
3 Proper Tire Size, Type and Load Capacity (or Load Range)
3 Tire Size Designations
5 The Sidewall Story
8 Speed Symbol
9 Uniform Tire Quality Grading (UTQG) Standards
10 Tire Registration and Recall Information
PROPER TIRE INFLATION AND VEHICLE LOADING
11 Proper Inflation is Critical
13 When to Check Inflation Pressure
13 Continuous Inflation Pressure Loss
14 Additional Tire Pressure Recommendations
15 Proper Tire Loading
REGULAR TIRE ROTATION
16 Rotation Patterns
REGULAR TIRE INSPECTION
18 Tire Inspection Guidelines
20 Tire Service Life
PROPER TIRE REPAIR
21 Have Your Tire Repaired Properly
23 Vehicle Original Equipment Temporary Tire Mobility Kits
23 Aftermarket Sealants
VEHICLE CONDITION, ALIGNMENT AND MAINTENANCE
24 Maintenance Conditions
25 Additional Conditions Affecting Tread Wear
26 Spare Tire Maintenance
26 Tire Storage Recommendations
27 Cleaning Tires
GOOD DRIVING HABITS
28 Road Hazard and Impact Damage
28 Sudden Vibration or Ride Disturbance
28 Tire Spinning
29 Wet Weather Driving
29 Winter/Snow Conditions
TIRE REPLACEMENT GUIDELINES
32 The Right Tire for the Vehicle
33 Self-Supporting Runflat Tires
33 Tire Mixing
34 Replacing Less Than Four Tires
34 Used Tires
TABLE OF CONTENTS
2
This booklet provides an understanding of the many factors essential to the
proper care and service of passenger and light truck tires. This booklet is not
all inclusive. Questions pertaining to specific products and/or vehicle fitments
should be addressed to the vehicle manufacturer, tire manufacturer or tire
dealer.
TIRE INFORMATION AND SERVICE ASSISTANCE
When you have a question about tires, there are various sources
of information available. The U.S. Tire Manufacturers Association’s
website, www.USTires.org, provides information on tire care and safety
and publications for consumers. The National Highway Traffic Safety
Administration’s website, www.safercar.gov has a wide range of tire related
information including information on tire labeling, tire ratings, and tire
maintenance. Also, tire manufacturer’s and tire retailer’s websites will often
contain a considerable amount of helpful tire information.
The Most Important Factors in Tire Safety, Performance and Service Life are:
Proper Tire Size, Type and Load Capacity (or Load Range)
Proper Inflation Pressure
Proper Vehicle Loading
Regular Tire Rotation
Regular Inspection
Proper Tire Repair
Vehicle Condition, Alignment and Maintenance
Good Driving Habits
Your local tire retailer, who has specialized tire knowledge and experience, is
an excellent resource when you have a question about tires or require service
assistance. Tire service professionals can provide you with proper tire service
including inspection, replacement and repair.
Tire Care and Safety
3
Note: Pickups, vans, sport ulity vehicles, and other vehicles that might be
perceived as a “light truck” are oen equipped with P-Metric and Metric re
sizes. Check the vehicle re placard to see which type of re is specied for
the vehicle.
BASIC TIRE INFORMATION
Proper Tire Size, Type and Load Capacity (or Load Range)
There are a large number of tires for passenger cars and light trucks intended
to meet the needs of a wide variety of consumers, vehicles and operating
conditions. Selecting and utilizing the proper tire starts with an understanding
of the basics of tire size, type and load capacity (or load range), which is
presented in this section. In addition, there is an explanation of speed ratings,
determining a tire manufacture date and a guide to other information found
on the sidewalls of most passenger and/or light truck tires.
Tire Size Designations
Most passenger and light truck tires have tire size designations such as the
following:
Passenger
4
Tire Size Designations Continued
Light Truck
LIGHT TRUCK
Aspect Ratio - In a tire size designation, the aspect ratio is the ratio of the tire
section height to section width. Aspect ratios are also referred to as “series”
and “profile” numbers. In the example shown of a tire with an aspect ratio of
60, the section height of the tire is 60% of the section width. Aspect ratios
typically range from 30 to 80.
5
The Sidewall Story
Tires have very useful information molded onto their sidewall. It shows the
brand and model name of the tire, its size, whether it is tubeless or tube type,
the maximum load and the maximum inflation, safety warning(s), and much
more.
P225/60R16 97T – (See Passenger Tire on page 6) Size marking and service
description (load index and speed symbol) for a P-Metric speed-rated
passenger tire.
LT245/75R16 120/116Q Load Range E – (See Light Truck Tire on page 6) Size
marking, service description (load index and speed symbol) and load range for
a metric light truck tire. The load range identifies the tire’s load and inflation
limits.
Load Index - The load index is a numerical code associated with the maximum
load a tire can carry. The load index should not be used independently to
determine replacement tire acceptability for load capacity. (See page 32 for
replacement tire guidelines.)
Speed Symbol - The speed symbol is also known as a “speed rating.” See page 8.
Max Load 730 kg (1609 lbs) at 300 kPa (44 psi) Max Pressure -
(See Passenger Tire on page 6) indicates maximum load and maximum cold
inflation pressure of the tire. Sidewall markings are given in both metric and
English units. Follow tire inflation pressure recommendations on the vehicle
tire placard, certification label or in the owner’s manual.
Max Load Single 1380 kg (3042 lbs) at 550 kPa (80 psi) Cold
Max Load Dual 1260 kg (2778 lbs) at 550 kPa (80 psi) Cold -
(See Light Truck Tire on page 6) indicates the maximum load of the tire and
corresponding maximum cold inflation pressure for that load when used in a
single or dual configuration. Sidewall markings are given in both metric and
English units. Follow tire inflation pressure recommendations on the vehicle
tire placard, certification label or in the owner’s manual.
DOT MA L9 ABCD 0309 - The “DOT” symbol certifies the tire manufacturer’s
compliance with U.S. Department of Transportation (U.S. DOT) tire safety
performance standards. Next to these letters is the tire identification number
(TIN) - also known as the tire “serial” number. Since the year 2000, the last four
digits are numbers identifying the week and year of manufacture (Example:
“0309” means third week of the year 2009.)
Over the years and in the future, the TIN found on the tire may be different.
6
Light Truck Tire
L
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Light truck tire
Nominal width of the tire
in millimeters
Aspect Ratio
(ratio of height to width)
Radial Construction
Rim Diameter Code
Load Range
Load Index
(single/dual) and
Speed Symbol
Maximum load carrying
capacity at maximum
cold inflation pressure
(single and dual load)
T
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1
DOT Tire Identification
Number
Tire ply composition
and material used
B
R
A
N
D
N
A
M
E
Tubeless
Passenger Tire
7
DOT TIN Description
TREADWEAR 600 TRACTION A TEMPERATURE B – Treadwear, traction,
and temperature are quality grades established and required by U.S. DOT
under the Uniform Tire Quality Grading Standards (UTQG). See page 9.
Plies/Fabric Information - The ply/fabric information identifies the number
of plies and type of cord materials in the tire tread and sidewall areas.
Radial - A tire with a radial construction must show the word “RADIAL” on
the sidewall. A radial tire is also indicated by the character “R” in the size
designation.
Tubeless - The tire must be marked either “tubeless” or “tube type.”
M + S - This mark is commonly found on all-season and winter tires. In
several formats, the letters “M” and “S” indicate the tire is intended for
limited mud and snow service. Other formats include: “MS,” “M/S,” or
“M&S.”
Mountain Snowflake Symbol - This mark is found on winter/snow tires that
meet the USTMA definition for passenger and light truck tires
for use in severe snow conditions. These tires are marked on at
least one sidewall with the letters “M” and “S” plus a mountain/
snowflake pictograph.
8
M M 81 130
N N 87 140
P P 93 150
Q Q 99 160
R R 106 170
S S 112 180
T T 118 190
U U 124 200
H H 130 210
V V 149 240
W W 168 270
Y Y 186 300
(Y) -- >186 >300
* In standardized laboratory tests that relate to highway speeds. Actual tire speed and performance
capability depend on factors such as inflation pressure, load, tire condition, wear, and driving conditions.
** Any tire having a maximum speed capability above 149 mph (240 km/h) may, at the tire man-
ufacturer’s discretion, include a “Z” in the size designation (i.e. P275/40ZR17). For tires having a
maximum speed capability above 186 mph (300 km/h), a “Z” must appear in the size designation
and must include a service description with a “(Y).”
Consult the tire manufacturer for speed capability when there is no service description or speed
symbol marked on the tire.
Examples:
P275/40ZR17 max speed > 149 mph - consult tire mfr.
P275/40R17 93W max speed = 168 mph
P275/40ZR17 93W max speed = 168 mph
P275/40ZR17 93Y max speed = 186 mph
P275/40ZR17 (93Y) max speed > 186 mph - consult tire mfr.
Speed Symbols
Speed
Symbol
Speed
Rating
Speed Category*
MPH KM/H
Speed Symbol
The speed symbol, also known as a speed rating, indicates the speed category
associated with the tire’s maximum speed capability. Speed ratings are
based on laboratory tests that relate to performance on the road, but are
not applicable if tires are under inflated, over loaded, worn out, damaged, or
altered.
Although a tire may be speed rated, USTMA does not endorse the operation
of any vehicle in an unsafe or unlawful manner. Furthermore, tire speed
ratings do not imply that a vehicle can be safely driven at the maximum
speed for which the tire is rated, particularly under adverse road and weather
conditions or if the vehicle has unusual characteristics. Consult the tire
manufacturer for speed capability when there is no service description or
speed symbol marked on the tire.
ZR**
9
Uniform Tire Quality Grading (UTQG) Standards
The National Highway Traffic Safety Administration (NHTSA) established
the Uniform Tire Quality Grading Standards as a way to assist the consumer
to compare various tires. UTQG applies to the vast majority of passenger
car tires (excluding tires such as winter-type snow tires). NHTSA sets the
standards that rate the relative performance of tires based on three criteria:
treadwear, traction and temperature. The grades are molded on the tire
sidewall. Replacement tires also have a label affixed to the tread that lists and
explains these grades. A vehicle’s engine type, transmission type, gear ratios,
driving styles, road surface, inflation pressure, and other factors can affect
actual performance of the tire from one vehicle to another.
The UTQG tire characteristics are as follows:
TREADWEAR - The TREADWEAR grade is a comparative rating based on the
wear rate of the tire when tested under controlled conditions on a specified
government test course. In the example shown, the TREADWEAR grade is
600, which means it would wear twice as well on the government course
as a tire graded 300. The relative performance of tires depends upon the
actual conditions of their use and may depart significantly from the norm
due to variations in driving habits, service practices and differences in road
characteristics and climate.
TRACTION - The TRACTION grades, from highest to lowest, are AA, A,
B, and C and they represent the tire’s ability to stop on wet pavement as
measured under controlled conditions on specified government test surfaces
of asphalt and concrete. The TRACTION grade assigned is based on braking
(straight ahead) traction tests and does not include cornering (turning)
traction.
TEMPERATURE - The TEMPERATURE grades are A (the highest), B and C,
representing the tire’s resistance to the generation of heat and its ability to
dissipate heat when tested under controlled conditions on a specified indoor
laboratory test wheel. The TEMPERATURE grade is established for a tire that
is properly inflated and not over loaded. Excessive speed, under inflation,
or over loading, either separately or in combination, can cause heat buildup
which may result in tire damage and/or tire failure.
In addition to the UTQG standards, all passenger car tires must conform to
federal performance safety requirements.
UTQG Tire Marking Example
10
Tire Registration and Recall Information
Registraon of res is an important step to complete when placing them into
service. Registraon enables manufacturers to contact the consumer in the
event of a recall. At the point of sale, consumers should be provided a re
registraon card. This informaon should be completed and submied as
soon as possible. USTMA re manufacturer members also provide online re
registraon forms that can be submied electronically.
Consumer contact informaon and DOT Tire Idencaon Numbers (TIN) are
necessary for registraon. In addion, DOT TINs are necessary to determine
whether a re is subject to a recall. Visit www.USTires.org for links to USTMA
member re registraon websites and for a re recall lookup tool.
11
PROPER TIRE INFLATION AND VEHICLE LOADING
The recommended inflation pressures for tires are specified in PSI (pounds
per square inch) or kPa (kilopascals) as indicated on the vehicle tire placard,
certification label or in the owner’s manual. Never set tire inflation pressures
below the recommended inflation pressure found on the vehicle tire placard,
certification label or owner’s manual. Under inflation causes excessive heat
build-up and internal structural damage that may lead to a tire failure, including
tread/belt separation, even at a later date. Do not exceed the maximum
inflation pressure shown on the tire sidewall. Over inflated tires (over the
maximum molded on the tire sidewall) are more likely to be cut, punctured or
damaged by sudden impact from hitting an obstacle, such as a pothole.
Example of a Vehicle Tire Placard Example of a Vehicle Certification Label
Proper Inflation is Critical
Inflation pressure enables a tire to support the load and to control the vehicle,
therefore proper inflation is critical. With the right amount of inflation
pressure, the vehicle and the tires will achieve their optimum performance.
In addition to tire safety, this means your tires will wear longer and improve
vehicle fuel consumption. Note that some vehicles may have different cold
inflation pressures for tires on the front and rear axles.
Driving on tires with improper inflation pressure is dangerous.
Under inflation causes excessive heat build-up and internal structure
damage.
Over inflation makes it more likely for tires to be cut, punctured or broken
by sudden impact.
These situations can cause a tire failure, including tread/belt separation, even at
a later date, which could lead to an accident and serious personal injury or death.
Consult the vehicle tire placard, certification label or the owner’s manual for the
recommended inflation pressures.
12
It is impossible to determine whether radial tires are properly inflated just
by looking at them. You must use a tire gauge to properly check the inflation
pressure. Motorists should have their own gauge and keep it in the vehicle.
One of these tires is dangerously under inflated. You cannot tell just by
looking.
Properly Inflated 50% Under Inflated
Check inflation pressure with an accurate tire gauge. A gauge calibrated in
1 psi increments up to 60 psi is sufficient for most passenger tires. A dual
head gauge calibrated in 2 psi increments up to 100 psi is sufficient for light
truck tires. Even if it is difficult to check the inflation pressures of inside tires
in dual fitments, it is imperative that these inflation pressures be checked
and properly maintained because the inside dual tires are subjected to more
severe operating conditions, such as:
High heat exposure, due to close proximity to brakes
Lower air circulation to assist in cooling
Crowned road surfaces (which can cause inside dual tires to support
more of the load than the outside dual tires)
Mechanical and Digital Style Gauges
NOTE
The pressure indicated on the tire sidewall is the maximum allowed in the tire,
irrespective of the vehicle. Follow the vehicle manufacturer’s recommendations for
inflation pressure found on the vehicle tire placard, certification label or in the owner’s
manual.
13
When to Check Inflation Pressure
Check inflation pressure when tires are cold, that is, when the vehicle has
been parked for at least 3 hours or has been driven less than one mile at
moderate speed. The inflation pressure in all tires, including the spare tire
and inside duals, should be checked with an accurate tire gauge at least
once a month. Additional checks should be made before long trips, carrying
heavy loads, towing a trailer and any time high speeds are anticipated. This
includes vehicles equipped with a Tire Pressure Monitoring System (TPMS).
Maintaining proper inflation pressure maximizes fuel economy and optimizes
overall tire performance.
Never “bleed” or reduce inflation pressure when tires are hot from driving, as
it is normal for pressures to increase above recommended cold pressures. If a
hot tire pressure reading is at or below recommended cold inflation pressure,
it may be dangerously under inflated. In this case, immediately determine the
cause and/or have the tire checked by a tire service professional.
Passenger and light truck tires may lose 1 to 2 psi inflation pressure per
month under normal conditions and 1 to 2 psi for every 10 degrees F
temperature drop. If a tire continually loses more than 2 psi per month, have
it checked by a tire service professional. Significant changes in altitude or
temperature will result in changes in inflation pressure and will require an
adjustment.
Continuous Inflation Pressure Loss
Any tire that continually requires re-inflation is a serious safety risk. The
cause may be a puncture, road hazard damage, leaking valve, corroded or
damaged rim, tire mounting damage or other irregular condition. Continuous
use of a tire in an under inflated condition will result in heat build-up and
internal tire damage. This may result in a tire failure, including tread/belt
separation. Tires that continuously require re-inflation should be inspected
thoroughly by a tire service professional and be properly serviced or replaced
immediately.
Inflating an unsecured tire is dangerous. If it bursts, it could be hurled into the
air with explosive force resulting in serious personal injury or death.
Never inflate a tire unless it is secured to a vehicle, tire mounting machine or
other restraining device.
14
Additional Tire Pressure Recommendations
Dual Tire Assemblies - For vehicles equipped with dual tire assemblies (duals),
if one of the dual tires becomes significantly under inflated or flat, the other
tire will carry the load for both tires, resulting in an over loaded condition for
both tires. Both tires should be inspected by a tire service professional for
damage.
Tire Pressure Monitoring Systems (TPMS) - It is still important to check
inflation pressure at least once a month, even on vehicles that are equipped
with a TPMS. Tire pressure monitoring systems are designed to be beneficial
and accurate. However, a TPMS should not be solely relied on for inflation
pressure maintenance since some systems may have limitations, such as:
Lack of warning of low inflation pressure until one or more tires are as
much as 25% below the vehicle manufacturer recommendations.
May only detect inflation pressure differences between tires (in other
words, if all tires are losing inflation pressure at the same rate, it is
possible that the TPMS will not adequately warn of inflation pressure
loss).
May not warn of rapid inflation pressure loss in a single tire.
Under inflation (prior to a TPMS warning) is increasingly dangerous at
high speeds, heavy vehicle loads, extended distances and at high ambient
temperatures.
Spare Tire Inflation Pressure - Full-size and temporary spare tire inflation
pressure should be checked monthly and before any long trips. Use an
accurate gauge. T-type temporary spare tires require 60 psi (420 kPa). When
adjusting inflation pressure in T-type tires, do so in small amounts since the
tire is smaller and the pressure level changes rapidly. Do not over inflate.
Valve Caps - Always cover the valve stem with a sealing cap. This helps
prevent moisture, dirt and other contaminants from entering the valve core,
as well as providing an additional seal.
Inflation Pressure for Off-Road Use - Inflation pressures for tires used in
most off-road situations should be the same as those for highway driving. If
a lower inflation pressure is used to gain additional flotation/traction at low
speeds, tires must be re-inflated before resuming driving on the highway or at
higher speeds, whether on- or off- road.
Using Nitrogen Inflation - Nitrogen may be offered as an alternative to air
for tire inflation. Nitrogen is an inert (non-flammable) gas - basically, nothing
more than dry air with oxygen removed (air contains about 78% nitrogen).
15
For normal tire service applications, nitrogen inflation is not necessary.
However, nitrogen inflation is permissible as its properties may contribute
to minor reductions in inflation pressure loss. Nevertheless, several other
sources of pressure leaks, such as punctures, tire/rim interface (bead), valve,
valve/rim interface, and the wheel, may negate the benefit of nitrogen.
Nitrogen and air can be mixed in any and all proportions. Nitrogen filled tires
can and should have air added whenever nitrogen is not readily available, to
maintain proper inflation as specified by the vehicle manufacturer.
Proper Tire Loading
To avoid over loading tires, maintain the proper inflation pressure and never
exceed the vehicle’s load capacity, Gross Axle Weight Ratings (GAWR) or
the Gross Vehicle Weight Rating (GVWR) stated on the vehicle tire placard,
certification label or the owner’s manual. The vehicle load must also be
distributed so that no individual axle, tire or dual assembly is over loaded.
The maximum load for each tire
is molded on the tire sidewall
(along with the maximum
inflation pressure for that load).
Never exceed the maximum
limits on the tire or the rim/
wheel.
For improved fuel efficiency,
reduce vehicle weight as
much as possible by removing
unnecessary items from your
cargo storage areas (in addition
to keeping tires properly
inflated).
Consult your vehicle owner’s
manual for load recommenda-
tions and special instructions
(such as trailer towing).
Under inflation and/or over loading of a tire
causes excessive heat build-up and internal
structural damage. This may cause a tire
failure, including tread/belt separation,
even at a later date, which can lead to an
accident and serious personal injury or
death.
Over loading a vehicle can have other serious
safety consequences such as suspension or
wheel failure, increased braking distance or
brake failure (particularly on steep grades),
and adverse vehicle handling/stability.
Consult the vehicle tire placard,
certification label or owner’s manual for the
recommended vehicle load limits and tire
inflation pressures.
NOTE
Whether inflated with air or nitrogen, regular inflation pressure maintenance remains
critical and necessary. Use of nitrogen alone is not a replacement for regular inflation
pressure maintenance.
16
REGULAR TIRE ROTATION
Rotation Patterns
Tire rotation procedures are established to equalize the tread wear for each
tire to prolong tread life. By regularly changing a tire to another position on
the vehicle, any abnormal wear patterns that were starting to develop may be
corrected.
Before rotating tires, always consult the vehicle and/or tire manufacturer
for specific recommendations regarding rotation. If no rotation period is
specified, tires should be rotated every 5,000 to 8,000 miles or at any sign of
uneven wear. The first rotation is the most important. If tires show uneven
tread wear, check for and correct any misalignment, imbalance, or other
mechanical problems before rotation. Any vehicle showing a tendency for
wear differential should have tires rotated more often.
Many vehicle manufacturers recommend replacing all tires on the vehicle
at the same time. This makes rotation even more important for maintaining
uniform tread depth and optimum tread wear of the entire set.
In the absence of vehicle manufacturer rotation recommendations, follow the
rotation patterns in the figures on page 17. Note that certain types of tires
cannot be rotated in the manner shown. Such tires may include directional
and asymmetrical tires. Also, some vehicles may have different sized tires
mounted on the front and rear axles, and these different sized tires have
rotation restrictions. For these special cases, check the recommendations in
the vehicle owner’s manual for proper rotation.
When tires are rotated, the inflation pressures must be adjusted for
the tires’ new positions in accordance with the vehicle manufacturer’s
recommendations; refer to the vehicle tire placard, certification label or
owner’s manual. See “Proper Tire Inflation and Vehicle Loading” on page 11.
If the vehicle has a matching full-size spare tire, it is recommended that it be
included in the tire rotation. Use one of the tire rotation patterns illustrated,
inserting the full-size spare at the right rear position. Always check and adjust
the inflation pressure of the full size spare when incorporating it into the
rotation pattern. Do not include a “Temporary Use” or T-type spare tire in any
of these rotation patterns.
17
Chapter 2, Page 18
FRONT
Vehicles with Dual Rear Wheels (Six-Tire Rotation)
FRONT
FRONT
FRONT
All Vehicles
FRONT
Rear and Four
Wheel Drive Vehicles
FRONT
Front Wheel Drive
Vehicles
FRONT
Rear and Four
Wheel Drive Vehicles
with Full Size Spare Tire
Full
Size
FRONT
All Vehicles
Front Wheel Drive Vehicles
with Full Size Spare Tire
Full
Size
FRONT
FRONT
Rear Tire Irregular Wear
Front Tire Irregular Wear
FIGURE 12: Typical Rotation Patterns When Tires are the Same Size and Type
Typical Rotation Patterns When Tires are the Same Size and Type
18
REGULAR TIRE INSPECTION
Tire Inspection Guidelines
In addition to maintaining proper inflation pressure, regularly inspect the tire
tread and sidewalls for irregular tread wear, cracking, scrapes, bulges, cuts,
snags, foreign objects or other damage resulting from use. Stones, glass, and
other foreign objects embedded in the tread should be removed to prevent
further damage. Even minor damage can lead to further injury and eventual
tire failure. Tires with excessive cracking on the tread or sidewall(s) should
be removed from service. This is typically caused by under inflation, over
loading, improper storage, and/or improper long-term parking.
Consumers should check their tire tread and sidewall areas during monthly
inflation pressure checks, looking for uneven or irregular tread wear or
other conditions as noted above. It is recommended that tires, including the
spare, be periodically inspected by a tire service professional during routine
maintenance intervals such as oil changes and tire rotations.
Replace tires when worn to 2/32” tread depth remaining anywhere on the
tread face. Built-in tread wear indicators or “wear bars”, which look like
narrow strips of smooth rubber across the tread, will appear on the tire when
the tread is worn to 2/32”. When a wear bar is flush with the tread surface,
the tire is worn out and it is time to replace it. If not replaced, loss of traction
in adverse weather conditions is more likely to occur.
Driving on damaged tires is dangerous. A damaged tire can suddenly fail
leading to situations that may result in serious personal injury or death.
Tires should be regularly inspected by a qualified tire service professional.
19
Tread Wear Indicators/Wear Bar
Based on the tread wear indicators on the tire above, the tire is worn out
In addition to wear out, if any of the following conditions below are found
when inspecting a tire, rim/wheel or valve, the item should be removed from
service. (Note: this list is not all-inclusive.)
Localized spot wear
Exposed wire cord or fabric material
Unrepairable punctures
Previous improper repairs
Bulges, blisters
Deep cuts/cracks
Run flat damage
Bent, cracked, corroded or damaged rim/wheel
Damaged valve and/or valve core
Consult a tire service professional with any questions or concerns regarding
tire, rim/wheel or valve conditions.
The “Penny Test” is an easy way to determine if your
tires are worn out. The test requires a penny. Place
the penny upside down into a tread groove of a tire. If
part of Lincoln’s head is covered by the tread, the tires
have the proper amount of tread. If you can see all of
Lincoln’s head, it is time to replace the tire.
20
Tire Service Life
It is important to have tires in good operating condition, thus tires may need
to be replaced because of service conditions long before the tread is worn
out. To determine if tires, including the spare, should remain in service,
it is recommended that they be periodically inspected by a tire service
professional during routine maintenance intervals like oil changes and tire
rotations. The service life of tires includes their overall condition and vehicle
usage factors, not just tread wear. All of these factors should be taken into
account when considering tire replacement.
Follow the vehicle and tire manufacturer’s specific recommendations, if any,
regarding tire service life and replacement. In order to determine the age of
the tire, look for the last four digits of the DOT tire identification number (see
“DOT TIN Description” on pages 6 and 7 for identifying the week and year of
manufacture).
Tire Service Life is Not Determined by Chronological Age - Tires are composed
of various materials, including rubber, having performance properties
essential to the proper functioning of the tire. These component properties
evolve over a combination of time, service and storage conditions. For each
individual tire, this change is affected by many elements such as temperature,
storage conditions, and conditions of use (e.g., load, speed, inflation pressure,
impacts and road hazard injury) to which a tire is subjected throughout its life.
Since service and storage conditions vary widely, accurately predicting the
service life of any specific tire based on calendar age is not possible. USTMA
is not aware of scientific or technical data that establishes or identifies a
specific minimum or maximum service life for passenger and light truck tires.
However, in some cases a tire or vehicle manufacturer may make a specific
tire replacement recommendation regarding its products. If so, the consumer
should consult the manufacturer with any questions with regard to following
the recommendation. Furthermore, any such recommendation should not be
considered a minimum service life for the tire.
Puncture repairs are limited to the tread area as generally depicted above.
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Puncture repairs are limited to the tread area as generally depicted above.
PROPER TIRE REPAIR
Tires driven even a short distance while under inflated may be damaged
beyond repair. Running a tire under inflated is like running the vehicle’s
engine without enough oil or coolant. It may seem to work fine for a time, but
serious permanent damage has occurred. Adding oil or coolant won’t repair
engine damage, and adding inflation pressure won’t fix tire damage. The tire
will remain seriously damaged and can still fail, even after inflation pressure is
corrected.
Have Your Tire Repaired Properly
Proper tire repairs should be performed by trained tire service professionals
using USTMA or tire manufacturer approved procedures. If a tire continually
loses inflation pressure or has lost all or most of its inflation pressure, it must
be removed from the wheel for a complete internal inspection to check for
damage. For vehicles equipped with dual tire assemblies (duals), if one of the
dual tires becomes significantly under inflated or flat, the other tire will carry
the load for both tires, resulting in an overloaded condition for both tires.
Consequently, both tires should be inspected by a tire service professional for
damage.
Never have a tire repaired with an injury that is greater than ¼ inch in
diameter. Do not repair an injury outside the puncture repair area.
Improperly repaired tires can fail while in service, such as by tread/belt
separation, which can lead to an accident and serious personal injury or death.
Tires must always be properly repaired as described in the USTMA wall chart,
“Puncture Repair Procedures for Passenger and Light Truck Tires.”
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Not all tires can be repaired. In addition to the USTMA puncture repair
procedures, there may be additional limitations based on individual tire
manufacturer repair policies. These may include the type of service such as
speed rating, load index, run-flat technology and commercial application.
When having a tire repaired, make sure the tire service professional:
Never performs a tire repair on-the-wheel
Never uses only a plug (stem)
Never uses only a patch
If a tire continually loses inflation pressure or has lost all or most of its
inflation pressure, it must be removed from the wheel for a complete
internal inspection to check for damage. Driving on damaged tires is
dangerous. A damaged tire can suddenly fail, including by tread/belt
separation, even at a later date, which can lead to an accident and serious
personal injury or death.
Never perform a tire repair without removing the tire from the wheel
assembly for an internal inspection. Do not perform an outside-in tire
repair or an on-the-wheel repair.
The photos above are an example of a tire that was operated in an
underinflated condition with a puncturing object that caused dangerous,
non-repairable damage to the innerliner and body ply material. This type
of damage would not have been visible from the outside of the tire. Every
tire must be removed from the wheel for an inspection and to assess
repairability.
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Vehicle Original Equipment Temporary Tire Mobility Kits
A temporary tire mobility kit may be supplied by the vehicle manufacturer
as an alternative to a spare or runflat tire in passenger car and light truck
applications. The temporary tire mobility kit is normally comprised of a
puncture sealant and a small air compressor or container of propellant.
Use of a temporary tire mobility kit:
Is not considered a repair to the tire
Only provides a temporary solution to promptly reach a service location
for professional inspection and possible repair of the affected tire. Refer
to tire manufacturer for specific guidelines regarding repairability and
warranty.
End-users of temporary tire mobility kits supplied as original equipment in
a passenger car or a light truck vehicle should always follow all instructions
provided by the vehicle manufacturer, including limits on the amount of
driving at reduced speeds allowed to safely reach a tire service location.
Aftermarket Sealants
The USTMA does not endorse aftermarket sealant products. Aerosol,
liquid, gel or other substances injected into a tire through the valve are not
considered proper repairs. Such products may:
be flammable and potentially explosive
damage the tire
void the tire manufacturer’s warranty
interfere with or damage tire pressure monitoring system sensors
Consult the tire manufacturer’s service recommendations and warranty
policy.
Flammable propellants and/or liquids in aftermarket sealants or aerosol
inflators may cause a tire to explode under certain circumstances. Never
introduce a flammable substance into a tire. Inform the tire service
TIRE SEALANTS AND BALANCING SUBSTANCES
Solvent-based liquids must not be used due to the possibility of
creating explosive mixtures of vapors in the tire, which may result in
serious injury or death.
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VEHICLE CONDITION, ALIGNMENT AND MAINTENANCE
There is a close relationship between several mechanical systems on a vehicle
and its tires. Tires, wheels, brakes, shock absorbers, drive train, steering and
suspension systems, among others, must all function together to perform safely
and comfortably and to give optimum tread wear. Improper or inadequate vehicle
maintenance can cause tires to wear rapidly and/or abnormally.
Maintenance Conditions
Improper Tire Inflation - For optimum service, use the inflation pressures
specified by the vehicle manufacturer on the vehicle tire placard, certification
label or owner’s manual. Under inflation may result in rapid and/or abnormal
tread wear, improper vehicle handling and decreased fuel economy. Over inflation
can result in rapid and/or abnormal tread wear, decreased traction and premature
wear of suspension components. See information “Proper Tire Inflation and
Vehicle Loading” on pages 11 through 15.
Vehicle Wheel Misalignment - If the vehicle wheels are not properly aligned,
tires will experience stresses as if they were constantly cornering. This will
cause increased and abnormal tread wear. A qualified mechanic should correct
misalignment of wheels. Front-wheel drive vehicles and those with independent
rear suspension require special attention with alignment of all four wheels.
Lack of Tire Rotation - Tire rotation procedures are established to equalize the
tread wear for each tire to prolong tread life. By regularly changing a tire to
another position on the vehicle, any abnormal wear patterns that were starting to
develop may be corrected. See “Regular Tire Rotation” on page 16).
Tire and Wheel Assembly Out-of-Balance - A tire and wheel assembly that is
out-of-balance can cause abnormal tread wear due to vibration and irregular road
contact which may be worse at specific speeds.
Damaged Wheels – In addition to resulting in possible loss of inflation, damaged
wheels can cause a tire to contact the road unevenly and cause abnormal tread
wear. Wheel damage may not be visually obvious and should be checked by a tire
service professional using proper measuring equipment.
Brakes in Disrepair - If not in proper working order, brakes can grab unevenly and
cause abnormal tread wear.
Worn Struts, Shock Absorbers - A worn strut or shock absorber will not properly
dampen vehicle motion and cause abnormal tread wear.
Worn or Loose Suspension and Steering Systems - Excessive wear and looseness
anywhere in the suspension and steering systems (such as tie-rod ends and ball
joints) can cause tire and wheel assemblies to move in ways in which they were
not designed, resulting in abnormal tread wear.
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Additional Conditions Affecting Tread Wear
Tread wear is affected by many different vehicle operating conditions.
Abnormal wear typically results from a combination of unsatisfactory conditions
and may make an accurate diagnosis of the cause(s) difficult. It is important
to identify the emergence of abnormal wear in its early stage and correct the
cause before valuable tire tread wear is lost. Most of the causes of abnormal
tread wear can be corrected. The causes can include excessive tire stresses due
to driving habits, road surfaces, terrain and axle position.
Driving Habits - The way a vehicle is driven has a great deal to do with tread
wear and safety. Observe posted speed limits and avoid hard stops, starts and
cornering. In addition, avoid potholes, objects on the road, and curbs (such as
hitting/forcing the tire against the curb when parking). The rate of tread wear
increases during hard cornering at both high and low speeds due to scuffing
caused by lateral forces, particularly on the front tires. Hard acceleration or
braking will also cause increased tread wear due to torque and weight transfer.
Typically the front tires are carrying a greater load and are doing the most
braking.
Road Surfaces/Terrain - Rapid or abnormal tread wear may be caused by
abrasive road surfaces such as those with sharp or coarse highway paving
materials. Areas that have numerous hills or curves can also lead to accelerated
tread wear.
Axle Position - The position of a tire on a vehicle determines what stresses the
tire will experience. The tires on the drive axle are affected by acceleration.
Depending on the vehicle, this can be the rear axle, the front axle or, in the case
of four-wheel drive, both axles. On front-wheel drive vehicles, the front axle
also steers the vehicle and performs most of the braking. Free-rolling, rear tires
may also experience some abnormal tread wear. Rotating tires on the vehicle
may help to minimize abnormal tread wear.
Examples of Abnormal Tread Wear
Diagonal Wear One-Sided Wear Both Shoulder Wear Center Wear
(All of the above tires are worn out)
Heel and Toe Wear Cupping Wear
Spare Tire Maintenance
Spare tire (full-size and temporary spare) inflation pressure should be checked
monthly and before any long trips. Use an accurate gauge. T-type temporary
spare tires require 60 psi (420 kPa). When adjusting inflation pressure in
T-type tires, do so in small amounts since the tire is smaller and the pressure
level changes rapidly. Do not over inflate.
Inspect the spare tire/rim/wheel periodically (i.e. during tire rotation intervals)
for any visible damage to the tire or corrosion on the wheel.
If the vehicle has a matching full-size spare tire, it is recommended that it be
included in the tire rotation. Always check and adjust the inflation pressure of
the full size spare when incorporating it into the rotation pattern.
There may be restrictions on speed, mileage and placement of a temporary
spare tire. Consult the vehicle owner’s manual for use of a temporary spare
tire.
T-type temporary spare tires should only be used with rims/wheels specifically
intended for them. Rims/wheels intended for use with T-type tires should not be
used with any other types of tires. A temporary spare tire and wheel assembly
should never be used on a vehicle with which it is not compatible. Never use
more than one temporary spare tire at a time.
Tire Storage Recommendations
Stored tires should be protected against environmental effects such as
sunlight, high heat, ozone and other potentially damaging conditions.
Weather checking/ozone cracking can occur during direct and extended
exposure to damaging effects of the environment, such as ozone and heat
from sunlight. Ozone cracking can also be caused by exposure to electric
motors, welding equipment, or other ozone generating sources. Tires with
severe weather checking/ozone cracking or any cracking that extends to the
tire casing cords/plies should be removed from service.
Follow the recommendations below when storing tires:
Store tires where the area is clean, dry and well ventilated, but with a
minimum of circulating air.
Store tires in an area with temperate ambient conditions (mild
temperatures, shaded or dark).
Store tires raised off a storage area’s floor surface to minimize exposure
to moisture or damage.
Avoid contact with petroleum-based products and/or other volatile
solvents or substances.
Store tires away from electric motors, battery chargers, generators,
welding equipment or other ozone generating sources.
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Indoor storage is recommended, however if tires must be stored outdoors:
Store tires where they are raised off the ground (or on storage racks) and
not in contact with heat absorbent surfaces.
Protect tires with an opaque, waterproof covering with some type of
vent openings to avoid creating a “heat box” or “steam bath” effect.
Tires Mounted on a Stored Vehicle - Store the vehicle such that all weight
is removed from the tires. If vehicle weight cannot be removed, unload the
vehicle to minimize the weight. Maintain the recommended tire inflation
pressure, including the spare. The surface where the vehicle is parked/stored
should be firm, reasonably level, well drained and clean. The vehicle should be
moved every three (3) months so the tire flex area is changed.
Returning Tires from Storage Back to Service - Before placing stored tires
back into service, a tire serviceprofessional should conduct a visual and tactile
inspection to be sure each tire is clean, dry, free of foreign objects, and/or
does not show signs of damage. See “Tire Inspection Guidelines” on page 18.
Once mounted on a rim/wheel, the tire (including the spare tire) should be
inflated to the recommended inflation pressure. See “Proper Tire Inflation and
Vehicle Loading” on page 11.
Cleaning Tires
Clean tires with soap and water and a soft bristle brush or a shop cloth.
Treating tires with incompatible dressings or harsh cleaning agents will hasten
oxidation and result in premature cracking. Never use petroleum-based tire
dressings, cleaners or other products. Use of a pressure washer or steam
cleaner may be damaging to the tire. Contact the tire manufacturer for
specific recommendations on cleaning tires.
GOOD DRIVING HABITS
The way you drive has a great deal to do with your tire service life and safety.
Therefore, in addition to proper tire maintenance, cultivate good driving
habits for your own benefit.
Observe posted speed limits.
Avoid fast starts, stops and turns.
Avoid potholes and objects on the road if possible.
Do not run over curbs or hit the tire against the curb when parking.
The rate of wear increases during hard cornering at both high and low speeds
due to scuffing caused by lateral forces, particularly on the front tires. Hard
acceleration or braking will also cause increased wear due to torque and
weight transfer.
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Road Hazard and Impact Damage
Punctures, cuts, snags, and other issues can lead to further damage if not
repaired in time. The tire must be demounted and carefully inspected to
determine whether it is repairable. Some road hazard damage may result
in gradual inflation pressure loss. If not corrected as soon as possible,
such damage can ruin tires that could otherwise have been repaired. For
information on proper tire repair, see page 21.
Impact damage to the tire may initially show little or no exterior evidence.
However, internal damage can progress with additional mileage and
eventually cause internal tire separation, detachment or sudden loss of
inflation. Impact damage may cause gradual inflation pressure loss. After
experiencing an impact, have the tire inspected by a tire service professional.
A rim bruise break (pinch shock) occurs when the tire strikes a rigid object
(like a curb or pothole) hard enough to crush the tire’s sidewall between the
rim flange and the rigid object. Vehicles operated off-road or in areas away
from paved roads can encounter many objects that can cause tire damage.
Careful inspection of the tires should be made after use in off-road service.
Sudden Vibration or Ride Disturbance
If the vehicle experiences a sudden vibration or ride disturbance and/or
there is a possibility the tires and/or vehicle have been damaged, gradually
reduce speed. Do not abruptly brake or turn. Drive with caution until you can
safely pull off the road. Stop and inspect the tire. If the tire is under inflated
or damaged, deflate and replace it with the spare tire. If a cause cannot be
detected, the vehicle should be towed to the nearest vehicle or tire dealer for
an inspection.
Tire Spinning
The centrifugal forces created by a rapidly spinning tire can cause an
explosion by literally tearing the tire apart. These forces act on the complete
tire structure, and can be of such magnitude as to break the beads in addition
to rupturing the tire. Some vehicles are able to bring a tire to its centrifugal
force failing point in just 3 to 5 seconds.
Driving on damaged tires is dangerous. A damaged tire can suddenly fail
leading to situations that may result in serious personal injury or death. Tires
should be regularly inspected by a qualified tire service professional.
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When stuck on ice, snow, mud, or wet grass, the vehicle should be rocked
gently (alternately using forward and reverse gears) with the least amount
of wheel spinning. Repeatedly shift the gear lever from drive to reverse on
automatic transmissions or reverse to second on manual transmissions, while
applying gentle pressure to the accelerator. Vehicles with ABS or traction
control systems may have specific instructions in their owner’s manual.
Wet Weather Driving
Driving too fast on wet roads, through standing water or in the rain, can
cause your tires to hydroplane. This means that your tires travel on a film
of water rather than contacting the road. After a dry spell, rain can further
reduce traction from oil and other substances that have collected on the
roadway. In addition, leaves can hide moisture on a road surface, even
long after the rain has stopped. When roads are wet, slow down and drive
carefully.
Winter/Snow Conditions
Dedicated winter/snow tires are designed to provide enhanced traction and
handling capabilities in adverse winter driving conditions.
Every time the outside temperature drops 10 degrees Fahrenheit, the
inflation pressure inside your tires goes down about 1 to 2 psi. Never reduce
tire pressures in an attempt to increase traction on snow or ice. It does not
work and your tires will be more susceptible to damage from under inflation.
In snowy areas, many cities and counties have “snow emergency” regulations
which are invoked during heavy snowfalls. Check with authorities for the
rules in your area. Under some rules, motorists are subject to fines if they
block traffic and do not have winter tires on their vehicles. Slow down and
drive carefully in adverse winter driving conditions.
Excessive speed in a free-spinning tire can cause the
tire to explode from extreme centrifugal force. The
energy released by such an explosion is sufficient to
cause serious physical injury or death.
Never spin a tire above a speedometer reading of
35 mph (56 km/h). Never stand near a spinning tire.
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Mountain Snowflake Symbol - This mark is found on winter/snow tires that
meet the USTMA definition for passenger and light truck tires
for use in severe snow conditions. These tires are marked on at
least one sidewall with the letters “M” and “S” (see page 7) plus a
mountain/snowflake pictograph.
Winter/Snow Tire Application - It is always preferable to apply winter/snow
tires to all wheel positions, including duals, to maintain vehicle mobility and
control.
If winter/snow tires are applied to the front axle of a vehicle, winter/
snow tires must also be installed on the rear axle. Do not apply winter/
snow tires only to the front axle. This applies to all passenger and light
truck vehicles including front-wheel-drive, 4WD, and AWD vehicles.
If winter/snow tires are installed on the rear axle of any vehicle, it is
recommended (but not required) that they also be installed on the front
axle.
Studded Winter/Snow Tire Application - Studded winter/snow tires have
higher traction qualities under most winter weather conditions.
If studded winter/snow tires are installed on the front axle of any vehicle,
studded winter/snow tires must also be installed on the rear axle. Do not
apply studded winter/snow tires only to the front axle.
If studded winter/snow tires are installed on the rear axle of any vehicle,
it is strongly recommended that they should also be installed on the
front axle. Only if studded winter/snow tires are installed on all wheel
positions of a vehicle will optimum handling characteristics be achieved.
Some states prohibit the use of studded tires and many states have
seasonal limitations on their use. Before installing, check with state and
local regulations.
It is generally acceptable to apply a dedicated winter/snow tire with a lower
speed rating than the OE tire; however, the vehicle speed is to be restricted
to that of the replacement tire.
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Chains - Make sure chains are the proper size and type for your tires,
otherwise they may damage the tire sidewall and cause tire failure. If you
have dual tires on your vehicle, particular care must be taken to assure
adequate clearance between loaded tires to avoid damage from chains.
Consult a tire service professional or vehicle manufacturer for proper
application.
Installing winter/snow tires (studded or unstudded) only on the front axle may
cause the vehicle to experience adverse handling characteristics. This may
result in an accident, which could cause serious injury or death.
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TIRE REPLACEMENT GUIDELINES
The Right Tire for the Vehicle
When tires need to be replaced, do not guess what tire is right for the vehicle.
For the answer, refer to the vehicle tire placard and/or certification label,
usually located on the vehicle door edge, door post, glove box or fuel door.
Also, check the vehicle owner’s manual for any additional tire replacement
recommendations. The vehicle tire placard identifies the size of the tires,
including the spare, that were installed on the vehicle as original equipment
(OE). The placard also specifies the recommended cold inflation pressures
for the tires on the front/rear axles and for the spare. If the vehicle does not
have a vehicle tire placard or certification label, consult the vehicle owner’s
manual, vehicle manufacturer, or tire manufacturer.
EXAMPLE OF A EXAMPLE OF A
VEHICLE TIRE PLACARD VEHICLE CERTIFICATION LABEL
Replacement tires should be the same as the OE size designation, or
approved options, as recommended by the vehicle or tire manufacturer.
Never choose a replacement tire of a smaller tire size or with less load-
carrying capacity than the OE tire size at the specified vehicle placard
pressure. It is recommended that all four tires be of the same size, speed
rating, and construction (radial, non-radial). In some cases, the vehicle
manufacturer may require different sized tires for either the front or rear
axles.
Selecting a tire or rim/wheel other than that recommended by the vehicle
manufacturer is a complex process that requires extensive knowledge and
training. Consult a tire service professional.
NOTE
Before replacing tires, ALWAYS refer to and follow the vehicle manufacturer’s tire
replacement recommendations and restrictions.
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Self-Supporting Runflat Tires
Runflat tires have specific servicing requirements, such as product-specific
puncture repair or demounting/mounting procedures, which vary by vehicle
and tire manufacturer. Consult with the tire manufacturers for details. A
functioning tire pressure monitoring system (TPMS) must be used with runflat
tires. Never mix runflat tires with conventional tires unless in an emergency
situation on a limited, temporary basis.
Tire Mixing
It is recommended that all four tires be of the same size, load index
and speed rating. In some cases the vehicle manufacturer may require
different sized tires for either the front or rear axles. Never mix P-Metric
or Metric passenger tires with light truck tires, including C-Type
European Commercial tires, on the same vehicle.
Speed rated tire - If the vehicle tire placard and/or owner’s manual
specifies speed rated tires, the replacement tires must have the same
or higher speed rating to maintain vehicle speed capability. Tire speed
ratings do not imply that vehicles can be safely driven at the maximum
speed for which the tire is rated, particularly under adverse road and
weather conditions, or if the vehicle has unusual characteristics. Never
operate a vehicle in an unsafe or unlawful manner.
If replacement tires have lower speed capability than specified by the
vehicle manufacturer, the vehicle’s speed must be restricted to that of the
replacement tire. Also, vehicle handling could be affected. Consult the vehicle
manufacturer or the tire manufacturer for recommendations.
Four-wheel drive (4WD) and all-wheel drive (AWD) vehicles - If no
instructions for tire mixing appear in the vehicle owner’s manual, follow
these guidelines:
- Do not mix tire sizes. All four tires must be marked with the same
tire size, unless otherwise specified by the vehicle manufacturer. This
also applies to dedicated winter/snow tires.
- Do not mix tread pattern types such as all-terrain and all-season.
For use of dedicated winter/snow tires, see page 29.
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NOTE
In some cases, the vehicle manufacturer may specifically advise against replacing less
than all four tires. Always check and follow the recommendations in the vehicle owner’s
manual. For 4WD and AWD vehicles, even small differences in outside diameter may
cause drive-train damage or mechanical malfunction.
Driving on damaged tires is dangerous. A damaged tire can suddenly fail leading
to situations that may result in serious personal injury or death. Tires should be
regularly inspected by a qualified tire service professional.
Replacing Less Than Four Tires
When replacing tires on a vehicle, it is recommended and preferred that
all four tires be replaced at the same time for continued optimal vehicle
performance. However, for those cases where this is not feasible, below are
some general guidelines to consider when replacing less than four tires for a
light vehicle, whether it is one or two tires.
Replacing Two (2) Tires - When a pair of replacement tires is selected in
the same size and construction as those on the vehicle, the two newer
tires should be installed on the rear axle. Generally, new tires with deeper
tread will provide better grip and evacuate water more effectively, which
is important as a driver approaches hydroplaning situations. Placing greater
traction on the rear axle on wet surfaces is necessary to prevent a possible
oversteer condition and loss of vehicle stability.
Replacing One (1) Tire - Replacing a single tire on a vehicle can have an
adverse effect on suspension systems, gear ratios, transmission, and tire tread
wear. If single tire replacement is unavoidable, it is recommended that the
single new tire be paired with the tire that has the deepest tread and both
be placed on the rear axle. Placing greater traction on the rear axle on wet
surfaces is necessary to prevent a possible over steer condition and loss of
vehicle stability.
Used Tires
This information pertains to used passenger and light truck tires installed as
replacement tires or as equipped on a used vehicle.
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Once tires are applied to a vehicle and put into service (this includes spare
tires), they are considered “used.” There is a potential risk associated with the
installation of used tires that have an uncertain or unknown history of use,
maintenance or storage conditions. Such tires may have damage that could
eventually lead to tire failure.
Not all tire damage that can lead to tire failure is outwardly visible. For
instance, improper repairs or damage to a tire’s inner liner can only be
observed by inspecting the inside of the tire, demounted from the wheel. A
qualified tire service professional should inspect the internal and external
condition of a used tire prior to application. In the case of a used vehicle
purchased by a consumer, the only way to determine the condition of its tires
is to have them demounted by a tire service professional for the same type of
inspection.
U.S. Tire Manufacturers Association • 1400 K Street, NW, Suite 900 • Washington, DC 20005
www.USTires.org
© 2018 U.S. Tire Manufacturers Association