warning light GMC ACADIA 2021 Workshop Manual

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
266 Driving and Operating
Trailer Tires
Special Trailer (ST) tires differ from vehicle
tires. Trailer tires are designed with stiff
sidewalls to help prevent sway and to
support heavy loads. These features can
make it difficult to determine if the trailer
tire pressures are low only based on a visual
inspection.
Always check all trailer tire pressures before
each trip when the tires are cool. Low trailer
tire pressure is a leading cause of trailer tire
blow-outs.
Trailer tires deteriorate over time. The trailer
tire sidewall will show the week and year
the tire was manufactured. Many trailer tire
manufacturers recommend replacing tires
more than six years old.
Overloading is another leading cause of
trailer tire blow-outs. Never load your trailer
with more weight than the tires are
designed to support. The load rating is
located on the trailer tire sidewall.
Always know the maximum speed rating for
the trailer tires before driving. This may be
significantly lower than the vehicle tire
speed rating. The speed rating may be onthe trailer tire sidewall. If the speed rating is
not shown, the default trailer tire speed
rating is 105 km/h (65 mph).
Conversions and Add-Ons
Add-On Electrical Equipment
{Warning
The Data Link Connector (DLC) is used for
vehicle service and Emission Inspection/
Maintenance testing. See
Malfunction
Indicator Lamp (Check Engine Light) 0107
. A device connected to the DLC —such
as an aftermarket fleet or driver-behavior
tracking device —may interfere with
vehicle systems. This could affect vehicle
operation and cause a crash. Such devices
may also access information stored in the
vehicle’s systems.
Caution
Some electrical equipment can damage
the vehicle or cause components to not
work and would not be covered by the
vehicle warranty. Always check with your
dealer before adding electrical equipment.
Add-on equipment can drain the vehicle's
12-volt battery, even if the vehicle is not
operating.
The vehicle has an airbag system. Before
attempting to add anything electrical to the
vehicle, see Servicing the Airbag-Equipped
Vehicle 063 and
Adding Equipment to the Airbag-Equipped
Vehicle 063.

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Vehicle Care 267
Vehicle Care
General Information
General Information . . . . . . . . . . . . . . . . . . . 268
California Proposition 65 Warning . . . . . 268
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . . . . . 268
Accessories and Modifications . . . . . . . . . 268
Vehicle Checks
Doing Your Own Service Work . . . . . . . . 269
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270
Engine Compartment Overview . . . . . . . . 271
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276
Engine Oil Life System . . . . . . . . . . . . . . . . 278
Automatic Transmission Fluid . . . . . . . . . 279
Engine Air Filter Life System . . . . . . . . . . 279
Engine Air Cleaner/Filter . . . . . . . . . . . . . . 279
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 281
Engine Overheating . . . . . . . . . . . . . . . . . . . 285
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 286
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
Battery - North America . . . . . . . . . . . . . . . 288
All-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . . 289
Park Brake and P (Park) Mechanism Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289
Wiper Blade Replacement . . . . . . . . . . . . . 290
Windshield Replacement . . . . . . . . . . . . . . 290
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . 292
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . 292
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . 292
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 292
Electrical System
Electrical System Overload . . . . . . . . . . . . 292
Fuses and Circuit Breakers . . . . . . . . . . . . . 293
Engine Compartment Fuse Block . . . . . . 293
Instrument Panel Fuse Block . . . . . . . . . . 296
Rear Compartment Fuse Block . . . . . . . . . 298
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . 301
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 301
Summer Tires . . . . . . . . . . . . . . . . . . . . . . . . . 302
All-Terrain Tires . . . . . . . . . . . . . . . . . . . . . . . 302
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . 302
Tire Designations . . . . . . . . . . . . . . . . . . . . . . 304
Tire Terminology and Definitions . . . . . 304
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . 307
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 308
Tire Pressure Monitor System . . . . . . . . . 309
Tire Pressure Monitor Operation . . . . . . . 310
Tire Inspection . . . . . . . . . . . . . . . . . . . . . . . . . 313
Tire Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . 313 When It Is Time for New Tires . . . . . . . . . 314
Buying New Tires . . . . . . . . . . . . . . . . . . . . . . 315
Different Size Tires and Wheels . . . . . . . . 316
Uniform Tire Quality Grading . . . . . . . . . . 316
Wheel Alignment and Tire Balance . . . . 318
Wheel Replacement . . . . . . . . . . . . . . . . . . . 318
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 319
Tire Sealant and Compressor Kit . . . . . . 320
Storing the Tire Sealant and
Compressor Kit . . . . . . . . . . . . . . . . . . . . . . 326
Tire Changing . . . . . . . . . . . . . . . . . . . . . . . . . 326
Compact Spare Tire . . . . . . . . . . . . . . . . . . . . 331
Jump Starting
Jump Starting - North America . . . . . . . . 332
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . . . . . . . . . . 334
Recreational Vehicle Towing . . . . . . . . . . . 335
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
Interior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 341
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343

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288 Vehicle Care
Checking Brake Fluid
With the vehicle in P (Park) on a level
surface, the brake fluid level should be
between the minimum and maximum marks
on the brake fluid reservoir.
There are only two reasons why the brake
fluid level in the reservoir may go down:
.Normal brake lining wear. When new
linings are installed, the fluid level goes
back up.
.A fluid leak in the brake hydraulic system.
Have the brake hydraulic system fixed.
With a leak, the brakes will not
work well.
Always clean the brake fluid reservoir cap
and the area around the cap before
removing it.
Do not top off the brake fluid. Adding fluid
does not correct a leak. If fluid is added
when the linings are worn, there will be too
much fluid when new brake linings are
installed. Add or remove fluid, as necessary,
only when work is done on the brake
hydraulic system.
{Warning
If too much brake fluid is added, it can
spill on the engine and burn, if the
engine is hot enough. You or others could
be burned, and the vehicle could be
damaged. Add brake fluid only when
work is done on the brake hydraulic
system.
When the brake fluid falls to a low level,
the brake warning light comes on. See Brake
System Warning Light 0108.
Brake fluid absorbs water over time which
degrades the effectiveness of the brake fluid.
Replace brake fluid at the specified intervals
to prevent increased stopping distance. See
Maintenance Schedule 0346.
What to Add
Use only GM approved DOT 3 brake fluid
from a clean, sealed container. See
Recommended Fluids and Lubricants 0354.
{Warning
The wrong or contaminated brake fluid
could result in damage to the brake
system. This could result in the loss of
(Continued)
Warning (Continued)
braking leading to a possible injury.
Always use the proper GM approved
brake fluid.
Caution
If brake fluid is spilled on the vehicle's
painted surfaces, the paint finish can be
damaged. Immediately wash off any
painted surface.
Battery - North America
The original equipment battery is
maintenance free. Do not remove the cap
and do not add fluid.
Refer to the replacement number on the
original battery label when a new battery is
needed. For replacement of the battery, see
your dealer.
Stop/Start System
The vehicle has a Stop/Start system to shut
off the engine to help conserve fuel. See
Stop/Start System0215.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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292 Vehicle Care
Headlamp Aiming
Front Headlamp Aiming
Headlamp aim has been preset and should
need no further adjustment.
If the vehicle is damaged in a crash, the
headlamp aim may be affected.
If adjustment to the headlamps is necessary,
see your dealer.
Bulb Replacement
For the proper type of replacement bulbs,
or any bulb changing procedure not listed in
this section, contact your dealer.
Caution
Do not replace incandescent bulbs with
aftermarket LED replacement bulbs. This
can cause damage to the vehicle electrical
system.
Halogen Bulbs
{Warning
Halogen bulbs have pressurized gas inside
and can burst if you drop or scratch the
bulb. You or others could be injured. Be
sure to read and follow the instructions
on the bulb package.
LED Lighting
This vehicle has several LED lamps. For
replacement of any LED lighting assembly,
contact your dealer.
Electrical System
Electrical System Overload
The vehicle has fuses and circuit breakers to
protect against an electrical system
overload.
When the current electrical load is too
heavy, the circuit breaker opens and closes,
protecting the circuit until the current load
returns to normal or the problem is fixed.
This greatly reduces the chance of circuit
overload and fire caused by electrical
problems.Fuses and circuit breakers protect power
devices in the vehicle.
Replace a bad fuse with a new one of the
identical size and rating.
If there is a problem on the road and a fuse
needs to be replaced, the same amperage
fuse can be borrowed. Choose some feature
of the vehicle that is not needed to use and
replace it as soon as possible.
Headlamp Wiring
An electrical overload may cause the lamps
to go on and off, or in some cases to
remain off. Have the headlamp wiring
checked right away if the lamps go on and
off or remain off.
Windshield Wipers
If the wiper motor overheats due to heavy
snow or ice, the windshield wipers will stop
until the motor cools and will then restart.
Although the circuit is protected from
electrical overload, overload due to heavy
snow or ice may cause wiper linkage
damage. Always clear ice and heavy snow
from the windshield before using the
windshield wipers.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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310 Vehicle Care
sequence will continue upon subsequent
vehicle start-ups as long as the malfunction
exists.
When the malfunction indicator is
illuminated, the system may not be able to
detect or signal low tire pressure as
intended. TPMS malfunctions may occur for
a variety of reasons, including the
installation of replacement or alternate tires
or wheels on the vehicle that prevent the
TPMS from functioning properly. Always
check the TPMS malfunction telltale after
replacing one or more tires or wheels on
your vehicle to ensure that the replacement
or alternate tires and wheels allow the
TPMS to continue to function properly.
SeeTire Pressure Monitor Operation 0310.
See Radio Frequency Statement 0371.
Tire Pressure Monitor Operation
This vehicle may have a Tire Pressure
Monitor System (TPMS). The TPMS is
designed to warn the driver when a low tire
pressure condition exists. TPMS sensors are
mounted onto each tire and wheel assembly, excluding the spare tire and
wheel assembly. The TPMS sensors monitor
the air pressure in the tires and transmit the
tire pressure readings to a receiver located
in the vehicle.
When a low tire pressure condition is
detected, the TPMS illuminates the low tire
pressure warning light located on the
instrument cluster. If the warning light
comes on, stop as soon as possible and
inflate the tires to the recommended
pressure shown on the Tire and Loading
Information label. See
Vehicle Load Limits
0 209.
A message to check the pressure in a
specific tire displays in the Driver
Information Center (DIC). The low tire
pressure warning light and the DIC warning
message come on at each ignition cycle
until the tires are inflated to the correct
inflation pressure. Using the DIC, tire pressure levels can be viewed. For additional
information and details about the DIC
operation and displays see
Driver
Information Center (DIC) (Base) 0115 or
Driver Information Center (DIC) (Midlevel and
Uplevel) 0117.
The low tire pressure warning light may
come on in cool weather when the vehicle is
first started, and then turn off as the vehicle
is driven. This could be an early indicator
that the air pressure is getting low and
needs to be inflated to the proper pressure.
A Tire and Loading Information label,
attached to your vehicle, shows the size of
the original equipment tires and the correct
inflation pressure for the tires when they
are cold. See Vehicle Load Limits 0209, for
an example of the Tire and Loading
Information label and its location. Also see
Tire Pressure 0307.
The TPMS can warn about a low tire
pressure condition but it does not replace
normal tire maintenance. See Tire Inspection
0 313, Tire Rotation 0313 and
Tires 0300.

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Vehicle Care 311
Caution
Tire sealant materials are not all the
same. A non-approved tire sealant could
damage the TPMS sensors. TPMS sensor
damage caused by using an incorrect tire
sealant is not covered by the vehicle
warranty. Always use only the GM
approved tire sealant available through
your dealer or included in the vehicle.
Factory-installed Tire Inflator Kits use a
GM-approved liquid tire sealant. Using
non-approved tire sealants could damage the
TPMS sensors. See Tire Sealant and
Compressor Kit 0320 for information
regarding the inflator kit materials and
instructions.
TPMS Malfunction Light and Message
The TPMS will not function properly if one
or more of the TPMS sensors are missing or
inoperable. When the system detects a
malfunction, the low tire pressure warning
light flashes for about one minute and then
stays on for the remainder of the ignition
cycle. A DIC warning message also displays.
The malfunction light and DIC warning
message come on at each ignition cycle until the problem is corrected. Some of the
conditions that can cause these to come
on are:
.One of the road tires has been replaced
with the spare tire. The spare tire does
not have a TPMS sensor. The malfunction
light and DIC message should go off after
the road tire is replaced and the sensor
matching process is performed
successfully. See
“TPMS Sensor Matching
Process” later in this section.
.The TPMS sensor matching process was
not done or not completed successfully
after rotating the tires. The malfunction
light and the DIC message should go off
after successfully completing the sensor
matching process. See "TPMS Sensor
Matching Process" later in this section.
.One or more TPMS sensors are missing or
damaged. The malfunction light and the
DIC message should go off when the
TPMS sensors are installed and the sensor
matching process is performed
successfully. See your dealer for service.
.Replacement tires or wheels do not match
the original equipment tires or wheels.
Tires and wheels other than those recommended could prevent the TPMS
from functioning properly. See
Buying
New Tires 0315.
.Operating electronic devices or being near
facilities using radio wave frequencies
similar to the TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning properly it
cannot detect or signal a low tire pressure
condition. See your dealer for service if the
TPMS malfunction light and DIC message
come on and stay on.
Tire Fill Alert (If Equipped)
This feature provides visual and audible
alerts outside the vehicle to help when
inflating an underinflated tire to the
recommended cold tire pressure.
When the low tire pressure warning light
comes on: 1. Park the vehicle in a safe, level place.
2. Set the parking brake firmly.
3. Place the vehicle in P (Park).
4. Add air to the tire that is underinflated. The turn signal lamp will flash.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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312 Vehicle Care
When the recommended pressure is
reached, the horn sounds once and the
turn signal lamp will stop flashing and
briefly turn solid.
Repeat these steps for all underinflated tires
that have illuminated the low tire pressure
warning light.
{Warning
Overinflating a tire could cause the tire
to rupture and you or others could be
injured. Do not exceed the maximum
pressure listed on the tire sidewall. See
Tire Sidewall Labeling 0302 and
Vehicle Load Limits 0209.
If the tire is overinflated by more than
35 kPa (5 psi), the horn will sound multiple
times and the turn signal lamp will continue
to flash for several seconds after filling
stops. To release and correct the pressure,
while the turn signal lamp is still flashing,
briefly press the center of the valve stem.
When the recommended pressure is reached,
the horn sounds once.
If the turn signal lamp does not flash within
15 seconds after starting to inflate the tire,
the tire fill alert has not been activated or is
not working. If the hazard warning flashers are on, the
tire fill alert visual feedback will not work
properly.
The TPMS will not activate the tire fill alert
properly under the following conditions:
.There is interference from an external
device or transmitter.
.The air pressure from the inflation device
is not sufficient to inflate the tire.
.There is a malfunction in the TPMS.
.There is a malfunction in the horn or turn
signal lamps.
.The identification code of the TPMS
sensor is not registered to the system.
.The battery of the TPMS sensor is low.
If the tire fill alert does not operate due to
TPMS interference, move the vehicle about
1 m (3 ft) back or forward and try again.
If the tire fill alert feature is not working,
use a tire pressure gauge.
TPMS Sensor Matching Process
Each TPMS sensor has a unique
identification code. The identification code
needs to be matched to a new tire/wheel
position after rotating the vehicle’s tires or
replacing one or more of the TPMS sensors. The TPMS sensor matching process should
also be performed after replacing a spare
tire with a road tire containing the TPMS
sensor. The malfunction light and the DIC
message should go off at the next ignition
cycle. The sensors are matched to the tire/
wheel positions, using a TPMS relearn tool,
in the following order: driver side front tire,
passenger side front tire, passenger side rear
tire, and driver side rear tire. See your
dealer for service or to purchase a relearn
tool. A TPMS relearn tool can also be
purchased. See Tire Pressure Monitor Sensor
Activation Tool at
www.gmtoolsandequipment.com or call
1-800-GM TOOLS (1-800-468-6657).
There are two minutes to match the first
tire/wheel position, and five minutes overall
to match all four tire/wheel positions. If it
takes longer, the matching process stops
and must be restarted.
The TPMS sensor matching process is:
1. Set the parking brake.
2. Place the vehicle in Service Mode. See Ignition Positions 0213.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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314 Vehicle Care
Use this rotation pattern when rotating
the tires.
Do not include the compact spare tire
in the tire rotation.
Adjust the front and rear tires to the
recommended inflation pressure on the
Tire and Loading Information label after
the tires have been rotated. SeeTire
Pressure 0307 and
Vehicle Load Limits 0209.
Reset the Tire Pressure Monitor System.
See Tire Pressure Monitor Operation
0 310. Check that all wheel nuts are properly
tightened. See
“Wheel Nut Torque”
under Capacities and Specifications
0 359, and “Removing the Flat Tire and
Installing the Spare Tire” underTire
Changing 0326.
{Warning
Rust or dirt on a wheel, or on the
parts to which it is fastened, can
cause wheel nuts to become loose
over time. The wheel could come off
and cause a crash. When changing a
wheel, remove any rust or dirt from
places where the wheel attaches to
the vehicle. In an emergency, a cloth
or paper towel can be used; however,
use a scraper or wire brush later to
remove all rust or dirt.
Lightly coat the inner diameter of the
wheel hub opening with wheel bearing
grease after a wheel change or tire
rotation to prevent corrosion or rust
buildup.
{Warning
Do not apply grease to the wheel
mounting surface, wheel conical
seats, or the wheel nuts or bolts.
Grease applied to these areas could
cause a wheel to become loose or
come off, resulting in a crash.
When It Is Time for New Tires
Factors, such as maintenance, temperatures,
driving speeds, vehicle loading, and road
conditions affect the wear rate of the tires.
Treadwear indicators are one way to tell
when it is time for new tires. Treadwear
indicators appear when the tires have only

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Vehicle Care 315
1.6 mm (1/16 in) or less of tread remaining.
SeeTire Inspection 0313 and
Tire Rotation 0313 for additional
information.
The rubber in tires ages over time. This also
applies to the spare tire, if the vehicle has
one, even if it is never used. Multiple factors
including temperatures, loading conditions,
and inflation pressure maintenance affect
how fast aging takes place. GM recommends
that tires, including the spare if equipped,
be replaced after six years, regardless of
tread wear. To identify the age of a tire, use
the tire manufacture date, which is the last
four digits of the DOT Tire Identification
Number (TIN) molded into one side of the
tire sidewall. The last four digits of the TIN
indicate the tire manufactured date. The
first two digits represent the week and the
last two digits, the year. For example, the
third week of the year 2020 would have a
4-digit DOT date of 0320. Week 01 is the
first full week (Sunday through Saturday) of
each year.
Vehicle Storage
Tires age when stored normally mounted on
a parked vehicle. Park a vehicle that will be
stored for at least a month in a cool, dry,
clean area away from direct sunlight to slow aging. This area should be free of grease,
gasoline, or other substances that can
deteriorate rubber.
Parking for an extended period can cause
flat spots on the tires that may result in
vibrations while driving. When storing a
vehicle for at least a month, remove the
tires or raise the vehicle to reduce the
weight from the tires.
Buying New Tires
GM has developed and matched specific
tires for the vehicle. The original
equipment tires installed were designed
to meet General Motors Tire
Performance Criteria Specification (TPC
Spec) system rating. When replacement
tires are needed, GM strongly
recommends buying tires with the same
TPC Spec rating.
GM's exclusive TPC Spec system
considers over a dozen critical
specifications that impact the overall
performance of the vehicle, including
brake system performance, ride and
handling, traction control, and tire
pressure monitoring performance. GM's
TPC Spec number is molded onto the
tire's sidewall near the tire size. If the
tires have an all-season tread design,
the TPC Spec number will be followed
by MS for mud and snow. See
Tire
Sidewall Labeling 0302 for additional
information.
GM recommends replacing worn tires in
complete sets of four. Uniform tread
depth on all tires will help to maintain
the performance of the vehicle. Braking
and handling performance may be
adversely affected if all the tires are not
replaced at the same time. If proper
rotation and maintenance have been
done, all four tires should wear out at
about the same time. However, if it is
necessary to replace only one axle set
of worn tires, place the new tires on
the rear axle. See Tire Rotation0313.
{Warning
Tires could explode during improper
service. Attempting to mount or
dismount a tire could cause injury or
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The Uniform Tire Quality Grading
(UTQG) system does not apply to deep
tread, winter tires, compact spare tires,
tires with nominal rim diameters of
10 to 12 inches (25 to 30 cm), or to some
limited-production tires.
While the tires available on General
Motors passenger cars and light trucks
may vary with respect to these grades,
they must also conform to federal
safety requirements and additional
General Motors Tire Performance
Criteria (TPC) standards.
Quality grades can be found where
applicable on the tire sidewall between
tread shoulder and maximum section
width. For example:
Treadwear 200 Traction AA Temperature A
All Passenger Car Tires Must Conform to
Federal Safety Requirements In Addition
To These Grades.
Treadwear
The treadwear grade is a comparative
rating based on the wear rate of the
tire when tested under controlledconditions on a specified government
test course. For example, a tire graded
150 would wear one and one-half (1½)
times as well on the government course
as a tire graded 100. The relative
performance of tires depends upon the
actual conditions of their use, however,
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. Those
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. Warning:
The traction grade assigned to this tire
is based on straight-ahead braking
traction tests, and does not include
acceleration, cornering, hydroplaning,
or peak traction characteristics.
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. Sustained high temperature can
cause the material of the tire to
degenerate and reduce tire life, and
excessive temperature can lead to
sudden tire failure. The grade C
corresponds to a level of performance
which all passenger car tires must meet
under the Federal Motor Safety
Standard No. 109. Grades B and A
represent higher levels of performance
on the laboratory test wheel than the
minimum required by law. Warning:
The temperature grade for this tire is
established for a tire that is properly
inflated and not overloaded. Excessive
speed, underinflation, or excessive
loading, either separately or in
combination, can cause heat buildup
and possible tire failure.