7.H: Indicates the tire’s speed rating. The speed rating denotes the
speed at which a tire is designed to be driven for extended periods
of time under a standard condition of load and inflation pressure.
The tires on your vehicle may operate at different conditions for load
and inflation pressure. These speed ratings may need to be adjusted
for the difference in conditions. The ratings range from 81 mph (130
km/h) to 186 mph (299 km/h). These ratings are listed in the
following chart.
Note: You may not find this information on all tires because it is not
required by federal law.
Letter rating Speed rating - mph (km/h)
M 81 mph (130 km/h)
N 87 mph (140 km/h)
Q 99 mph (159 km/h)
R 106 mph (171 km/h)
S 112 mph (180 km/h)
T 118 mph (190 km/h)
U 124 mph (200 km/h)
H 130 mph (210 km/h)
V 149 mph (240 km/h)
W 168 mph (270 km/h)
Y 186 mph (299 km/h)
Note: For tires with a maximum speed capability over 149 mph (240
km/h), tire manufacturers sometimes use the letters ZR. For those with
a maximum speed capability over 186 mph (299 km/h), tire
manufacturers always use the letters ZR.
8. U.S. DOT Tire Identification Number (TIN): This begins with
the letters “DOT” and indicates that the tire meets all federal
standards. The next two numbers or letters are the plant code
designating where it was manufactured, the next two are the tire
size code and the last four numbers represent the week and year the
tire was built. For example, the numbers 317 mean the 31st week of
1997. After 2000 the numbers go to four digits. For example, 2501
means the 25th week of 2001. The numbers in between are
identification codes used for traceability. This information is used to
contact customers if a tire defect requires a recall.
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9.M+S or M/S: Mud and Snow, or
AT: All Terrain, or
AS: All Season.
10. Tire Ply Composition and Material Used: Indicates the number
of plies or the number of layers of rubber-coated fabric in the tire
tread and sidewall. Tire manufacturers also must indicate the ply
materials in the tire and the sidewall, which include steel, nylon,
polyester, and others.
11. Maximum Load: Indicates the maximum load in kilograms and
pounds that can be carried by the tire. Refer to the Safety
Compliance Certification Label, which is located on the B-Pillar or
the edge of the driver’s door, for the correct tire pressure for your
vehicle.
12. Treadwear, Traction and Temperature Grades
• 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. For example, a tire graded 150
would wear one and one-half (1
1 2) times as well on the government
course as a tire graded 100.
• Traction: The traction grades, from highest to lowest are AA, A, B,
and C. The grades represent the tire’s ability to stop on wet pavement
as measured under controlled conditions on specified government test
surfaces of asphalt and concrete. A tire marked C may have poor
traction performance.
• 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.
13. Maximum Permissible Inflation Pressure: Indicates the tire
manufacturers’ maximum permissible pressure and/or the pressure at
which the maximum load can be carried by the tire. This pressure is
normally higher than the manufacturer’s recommended cold inflation
pressure which can be found on the Safety Compliance Certification
Label or Tire Label which is located on the B-Pillar or the edge of
the driver’s door. The cold inflation pressure should never be set
lower than the recommended pressure on the vehicle label.
The tire suppliers may have additional markings, notes or warnings such
as standard load, radial tubeless, etc.
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Additional information contained on the tire sidewall for “LT” type
tires
“LT” type tires have some additional
information beyond those of “P”
type tires; these differences are
described below:1. LT: Indicates a tire, designated
by the Tire and Rim Association
(T&RA), that is intended for
service on light trucks.
2. Load Range/Load Inflation
Limits: Indicates the tire’s
load-carrying capabilities and its
inflation limits.
3. Maximum Load Dual lb. (kg)
at psi (kPa) cold: Indicates
the maximum load and tire
pressure when the tire is used as a dual; defined as four tires on the
rear axle (a total of six or more tires on the vehicle).
4. Maximum Load Single lb. (kg) at psi (kPa) cold: Indicates the
maximum load and tire pressure when the tire is used as a single;
defined as two tires (total) on the rear axle.
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Information on “T” type tires
“T” type tires have some additional
information beyond those of “P”
type tires; these differences are
described below:
T145/80D16 is an example of a tire
size.
Note:The temporary tire size for
your vehicle may be different from
this example.
1. T:Indicates a type of tire,
designated by the Tire and Rim
Association (T&RA), that is
intended for temporary service
on cars, SUVs, minivans and
light trucks.
2. 145: Indicates the nominal
width of the tire in millimeters
from sidewall edge to sidewall edge. In general, the larger the
number, the wider the tire.
3. 80: Indicates the aspect ratio which gives the tire’s ratio of height to
width. Numbers of 70 or lower indicate a short sidewall.
4. D: Indicates a “diagonal” type tire.
R: Indicates a “radial” type tire.
5. 16: Indicates the wheel or rim diameter in inches. If you change
your wheel size, you will have to purchase new tires to match the
new wheel diameter.
Location of the tire label
You will find a Tire Label containing tire inflation pressure by tire size
and other important information located on the B-Pillar or the edge of
the driver’s door. Refer to the payload description and graphic in the
Vehicle loading — with and without a trailer section.
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TIRE PRESSURE MONITORING SYSTEM (TPMS)
Each tire, including the spare (if
provided), should be checked
monthly when cold and inflated to
the inflation pressure recommended
by the vehicle manufacturer on the
vehicle placard or tire inflation pressure label. (If your vehicle has tires
of a different size than the size indicated on the vehicle placard or tire
inflation pressure label, you should determine the proper tire inflation
pressure for those tires.)
As an added safety feature, your vehicle has been equipped with a tire
pressure monitoring system (TPMS) that illuminates a low tire pressure
telltale when one or more of your tires is significantly under-inflated.
Accordingly, when the low tire pressure telltale illuminates, you should
stop and check your tires as soon as possible, and inflate them to the
proper pressure. Driving on a significantly under-inflated tire causes the
tire to overheat and can lead to tire failure. Under-inflation also reduces
fuel efficiency and tire tread life, and may affect the vehicle’s handling
and stopping ability.
Please note that the TPMS is not a substitute for proper tire
maintenance, and it is the driver’s responsibility to maintain correct tire
pressure, even if under-inflation has not reached the level to trigger
illumination of the TPMS low tire pressure telltale.
The Tire Pressure Monitoring System complies with part 15 of the FCC
rules and with RSS-210 of Industry Canada. Operation is subject to the
following two conditions: (1) This device may not cause harmful
interference, and (2) This device must accept any interference received,
including interference that may cause undesired operation.WARNING: The Tire Pressure Monitoring System is NOT a
substitute for manually checking tire pressure. The tire
pressure should be checked periodically (at least monthly)
using a tire gauge, see Inflating your tiresin this chapter.
Failure to properly maintain your tire pressure could increase
the risk of tire failure, loss of control, vehicle rollover and
personal injury.
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Changing tires with TPMS
Each road tire is equipped with
a tire pressure sensor fastened
to the inside rim of the wheel.
The pressure sensor is covered
by the tire and is not visible
unless the tire is removed. The
pressure sensor is located
opposite (180 degrees) from the
valve stem. Care must be taken
when changing the tire to avoid
damaging the sensor.It is
recommended that you always have
your tires serviced by an authorized
dealer.
The tire pressure should be checked
periodically (at least monthly) using
an accurate tire gauge, refer to
Inflating your tires in this chapter.
Understanding your Tire Pressure Monitoring System (TPMS)
The Tire Pressure Monitoring System measures pressure in your four
road tires and sends the tire pressure readings to your vehicle. The Low
Tire Warning Lamp will turn ON if the tire pressure is 25% below the
pressure listed on the Tire Label located on the B-Pillar or the edge of
the driver’s door. Once the light is illuminated, your tires are under
inflated and need to be inflated to the manufacturer’s recommended tire
pressure. Even if the light turns ON and a short time later turns OFF,
your tire pressure still needs to be checked.
When your temporary spare tire is installed (if equipped)
When one of your road tires needs to be replaced with the temporary
spare (T-type spare/Mini spare or Dissimilar spare), the TPMS system
will continue to identify an issue to remind you that the damaged road
wheel/tire needs to be repaired and put back on your vehicle.
To restore the full functionality of the Tire Pressure Monitoring System,
have the damaged road wheel/tire repaired and remounted on your
vehicle. For additional information, refer to Changing tires with TPMS
in this section.
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When you believe your system is not operating properly
The main function of the Tire Pressure Monitoring System is to warn you
when your tires need air. It can also warn you in the event the system is
no longer capable of functioning as intended. Please refer to the
following chart for information concerning your Tire Pressure Monitoring
System:
Low Tire Pressure
Warning LightPossible cause Customer Action Required
Solid Warning Light Tire(s) under-inflated1. Check your tire pressure to
ensure tires are properly
inflated; refer to
Inflating your
tires in this chapter.
2. After inflating your tires to
the manufacturer’s
recommended inflation pressure
as shown on the Tire Label
(located on the edge of driver’s
door or the B-Pillar) the vehicle
must be driven for at least two
minutes over 20 mph (32 km/h)
before the light will turn OFF.
Spare tire in
use Your temporary spare tire is in
use. Repair the damaged road
wheel/tire and reinstall it on the
vehicle to restore system
functionality. For a description
on how the system functions,
refer to
When your temporary
spare tire is installed in this
section.
TPMS
malfunction If your tires are properly
inflated and your spare tire is
not in use and the light remains
ON, have the system inspected
by your authorized dealer.
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Low Tire Pressure
Warning LightPossible cause Customer Action Required
Flashing Warning
Light Spare tire in
useYour temporary spare tire is in
use. Repair the damaged road
wheel and re-mount it on the
vehicle to restore system
functionality. For a description
of how the system functions
under these conditions, refer to
When your temporary spare
tire is intalled
in this section.
TPMS
malfunction If your tires are properly
inflated and your spare tire is
not in use and the TPMS
warning light is still ON, have
the system inspected by your
authorized dealer.
When inflating your tires
When putting air into your tires (such as at a gas station or in your
garage), the Tire Pressure Monitoring System may not respond
immediately to the air added to your tires.
It may take up to two minutes of driving over 20 mph (32 km/h) for the
light to turn OFF after you have filled your tires to the recommended
tire pressure.
How temperature affects your tire pressure
The Tire Pressure Monitoring System (TPMS) monitors tire pressure in
each pneumatic tire. While driving in a normal manner, a typical passenger
tire inflation pressure may increase approximately 2 to 4 psi (14 to 28
kPa) from a cold start situation. If the vehicle is stationary over night with
the outside temperature significantly lower than the daytime temperature,
the tire pressure may decrease approximately 3 psi (20.7 kPa) for a drop
of 30° F (16.6° C) in ambient temperature. This lower pressure value may
be detected by the TPMS as being lower than the recommended inflation
pressure and activate the TPMS warning for low tire pressure. If the low
tire pressure warning light is ON, visually check each tire to verify that no
tire is flat. If one or more tires are flat, repair as necessary. Check air
pressure in the road tires. If any tire is underinflated, carefully drive the
vehicle to the nearest location where air can be added to the tires. Inflate
all the tires to the recommended inflation pressure.
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