air condition CHEVROLET SILVERADO 1500 2023 Service Manual

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico/Paraguay-16515119) - 2023 - CRC - 6/2/22
Vehicle Care 347
If Steam is Coming from the Engine
Compartment
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high
speed and you could be burned. Never
turn the cap when the cooling system,
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.
If No Steam is Coming from the Engine
Compartment
The ENGINE OVERHEATED STOP ENGINE or
the ENGINE OVERHEATED IDLE ENGINE
message, along with a low coolant
condition, can indicate a serious problem.
The 2.7L L4 engine will shut down
automatically if the ENGINE OVERHEATED
STOP ENGINE message displays.
If there is an engine overheat warning, but
no steam is seen or heard, the problem may
not be too serious. Sometimes the engine
can get a little too hot when the vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
.Tows a trailer; seeTrailer Towing0302.
If the ENGINE OVERHEATED STOP ENGINE or
the ENGINE OVERHEATED IDLE ENGINE
message appears with no sign of steam, try
this for a minute or so: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest fan
speed. Open the windows as necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or N (Neutral) and
let the engine idle.
If the temperature overheat gauge is no
longer in the overheat zone or an overheat
warning no longer displays, the vehicle can
be driven. Continue to drive the vehicle
slowly for about 10 minutes. Keep a safe
vehicle distance from the vehicle in front.
If the warning does not come back on,
continue to drive normally and have the
cooling system checked for proper fill and
function.
If the warning continues, pull over, stop, and
park the vehicle right away. If there is still no sign of steam and the
vehicle is equipped with an engine driven
cooling fan, push down the accelerator until
the engine speed is about twice as fast as
normal idle speed for at least five minutes
while the vehicle is parked. If the warning is
still there, turn off the engine and get
everyone out of the vehicle until it
cools down.
If there is no sign of steam, idle the engine
for five minutes while parked. If the warning
is still displayed, turn off the engine until it
cools down.
Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and
the ENGINE POWER IS REDUCED message
displays, an overheat protection mode which
alternates firing groups of cylinders helps to
prevent engine damage. In this mode, a loss
in power and engine performance will be
noticed. This operating mode allows the
vehicle to be driven to a safe place in an
emergency. Driving extended distances and/
or towing a trailer in the overheat
protection mode should be avoided.

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico/Paraguay-16515119) - 2023 - CRC - 6/2/22
348 Vehicle Care
If the engine or transmission detects an
impending hot fluid condition, then the
transmission may force upshifts to limit
temperatures. Downshifts may also be
prevented in this instance. Normal operation
may continue unless the display indicates
there is a hot condition and engine should
be idled.
Caution
After driving in the overheated engine
protection operating mode, the engine oil
will be severely degraded. Any repairs
performed before the engine is cool may
cause engine damage. Allow the engine
to cool before attempting any repair.
Repair the cause of coolant loss, change
the oil, and reset the oil life system. See
Engine Oil0338.
Engine Fan
If the vehicle has the Duramax diesel
engine, see the Duramax diesel supplement.
The vehicle has electric cooling fan(s). The
fans may be heard spinning at low speed
during most everyday driving. The fans may
turn off if no cooling is required. Under
heavy vehicle loading, trailer towing, high outside temperatures, or operation of the air
conditioning system, the fans may change
to high speed and an increase in fan noise
may be heard. This is normal and indicates
that the cooling system is functioning
properly. The fans will change to low speed
when additional cooling is no longer
required.
The electric engine cooling fans may run
after the engine has been turned off. This is
normal and no service is required.
Washer Fluid
What to Use
When windshield washer fluid needs to be
added, be sure to read the manufacturer's
instructions before use. Use a fluid that has
sufficient protection against freezing in an
area where the temperature may fall below
freezing.
Adding Washer Fluid
The vehicle has a low washer fluid message
on the DIC that comes on when the washer
fluid is low. The message is displayed for
15 seconds at the start of each ignition cycle.
When the WASHER FLUID LOW ADD FLUID
message displays, washer fluid will need to
be added to the windshield washer fluid
reservoir.
Open the cap with the washer symbol on it.
Add washer fluid until the tank is full. See
Engine Compartment Overview
0335 for
reservoir location.
Caution
.Do not use washer fluid that contains
any type of water repellent coating.
This can cause the wiper blades to
chatter or skip.
.Do not use engine coolant (antifreeze)
in the windshield washer. It can
damage the windshield washer system
and paint.
(Continued)

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico/Paraguay-16515119) - 2023 - CRC - 6/2/22
Vehicle Care 349
Caution (Continued)
.Do not mix water with ready-to-use
washer fluid. Water can cause the
solution to freeze and damage the
washer fluid tank and other parts of
the washer system.
.When using concentrated washer fluid,
follow the manufacturer instructions
for adding water.
.Fill the washer fluid tank only
three-quarters full when it is very cold.
This allows for fluid expansion if
freezing occurs, which could damage
the tank if it is completely full.
Brakes
Disc brake linings have built-in wear
indicators that make a high-pitched warning
sound when the brake linings are worn and
new linings are needed. The sound can come
and go or can be heard all the time when
the vehicle is moving, except when applying
the brake pedal firmly.
{Warning
The brake wear warning sound means
that soon the brakes will not work well.
That could lead to a crash. When the
brake wear warning sound is heard, have
the vehicle serviced.
Caution
Continuing to drive with worn-out brake
linings could result in costly brake
repairs.
Some driving conditions or climates can
cause a brake squeal when the brakes are
first applied, clearing up following several
applications. This does not mean something
is wrong with the brakes.
Properly torqued wheel nuts are necessary
to help prevent brake pulsation. When tires
are rotated, inspect brake linings for wear
and evenly tighten wheel nuts in the proper
sequence to torque specifications. See
Capacities and Specifications 0426.
Brake pads should be replaced as complete
axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not
return to normal height, or if there is a
rapid increase in pedal travel. This could be
a sign that brake service may be required.
Replacing Brake System Parts
Always replace brake system parts with
new, approved replacement parts. If this is
not done, the brakes may not work
properly. The braking performance can
change in many ways if the wrong brake
parts are installed or if parts are improperly
installed.
Brake Pad Life System
When to Change Brake Pads
This vehicle has a system that estimates the
remaining life of the front and rear brake
pads. Brake pad life is displayed in the
Driver Information Center (DIC), along with
a percentage for each axle. The system must
be reset every time the brake pads are
changed.
When the system has determined that the
brake pads need to be replaced, a message
will display, which may include mileage
remaining.

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
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370 Vehicle Care
Warning (Continued)
.Worn or old tires can cause a
crash. If the tread is badly worn,
replace them.
.Replace any tires that have been
damaged by impacts with
potholes, curbs, etc.
.Improperly repaired tires can cause
a crash. Only your dealer or an
authorized tire service center
should repair, replace, dismount,
and mount the tires.
.Do not spin the tires in excess of
56 km/h (35 mph) on slippery
surfaces such as snow, mud, ice,
etc. Excessive spinning may cause
the tires to explode.
All-Season Tires
This vehicle may come with all-season tires.
These tires are designed to provide good
overall performance on most road surfaces
and weather conditions. Original equipment
tires designed to GM's specific tire
performance criteria have a TPC specification
code molded onto the sidewall. Originalequipment all-season tires can be identified
by the last two characters of this TPC code,
which will be
“MS.”
Consider installing winter tires on the
vehicle if frequent driving on snow or
ice-covered roads is expected. All-season tires
provide adequate performance for most
winter driving conditions, but they may not
offer the same level of traction or
performance as winter tires on snow or
ice-covered roads. See Winter Tires0370.
Winter Tires
This vehicle was not originally equipped
with winter tires. Winter tires are designed
for increased traction on snow and
ice-covered roads. Consider installing winter
tires on the vehicle if frequent driving on ice
or snow covered roads is expected. See your
dealer for details regarding winter tire
availability and proper tire selection. Also,
see Buying New Tires 0383.
With winter tires, there may be decreased
dry road traction, increased road noise, and
shorter tread life. After changing to winter
tires, be alert for changes in vehicle
handling and braking. If using winter tires:
.Use tires of the same brand and tread
type on all four wheel positions.
.Use only radial ply tires of the same size,
load range, and speed rating as the
original equipment tires.
Winter tires with the same speed rating as
the original equipment tires may not be
available for H, V, W, Y, and ZR speed rated
tires. If winter tires with a lower speed
rating are chosen, never exceed the tire's
maximum speed capability.
All-Terrain Tires
This vehicle may have all-terrain or
mud-terrain tires. These tires provide good
performance on most road surfaces, weather
conditions, and for off-road driving. See
Off-Road Driving 0197.
The tread pattern on these tires may wear
more unevenly than other tires. Consider
rotating the tires more frequently than at
12 000 km (7,500 mi) intervals if irregular
wear is noted when the tires are inspected.
See Tire Inspection 0381.

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico/Paraguay-16515119) - 2023 - CRC - 6/2/22
Vehicle Care 377
Put the valve caps back on the valve
stems to keep out dirt and moisture.
Use only valve caps designed for the
vehicle by GM. TPMS sensors could be
damaged and would not be covered by
the vehicle warranty.
Tire Pressure Monitor System
The Tire Pressure Monitor System (TPMS)
uses radio and sensor technology to check
tire pressure levels. The TPMS sensors
monitor the air pressure in your tires and
transmit tire pressure readings to a receiver
located in the vehicle.
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 energy
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.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The
TPMS malfunction indicator is combined
with the low tire pressure telltale. When the
system detects a malfunction, the telltale
will flash for approximately one minute and
then remain continuously illuminated. Thissequence 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.
See
Tire Pressure Monitor Operation 0377.
See Radio Frequency Statement 0438.
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

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico/Paraguay-16515119) - 2023 - CRC - 6/2/22
378 Vehicle Care
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. SeeVehicle Load Limits
0 204.
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. If the vehicle has DIC
buttons, tire pressure levels can be viewed.
For additional information and details about
the DIC operation and displays, see Driver
Information Center (DIC) (Base Level) 0126 or
Driver Information Center (DIC) (Uplevel)
0
127.
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 shows
the size of the original equipment tires and
the correct inflation pressure for the tires
when they are cold. See Vehicle Load Limits
0 204, for an example of the Tire and
Loading Information label and its location.
Also see Tire Pressure 0375.
The TPMS can warn about a low tire
pressure condition but it does not replace
normal tire maintenance. See Tire Inspection
0 381, Tire Rotation 0382, and Tires0369.
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
(Continued)
Caution (Continued)
warranty. Always use only the GM
approved tire sealant available through
your dealer or included in the vehicle.
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 the 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.

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
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Vehicle Care 379
.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. SeeBuying
New Tires 0383.
.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.
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 (Continued)
Warning (Continued)
pressure listed on the tire sidewall. See
Tire Sidewall Labeling0371 and
Vehicle Load Limits 0204.
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.

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico/Paraguay-16515119) - 2023 - CRC - 6/2/22
380 Vehicle Care
.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 —Auto
Learn Function
Each TPMS sensor has a unique
identification code. The identification code
needs to be matched to a new tire/wheel
position after rotating the tires or replacing
one or more of the TPMS sensors. When a
tire is installed, the vehicle must be
stationary for about 20 minutes before the
system recalculates. The following relearn
process takes up to 10 minutes, driving at a
minimum speed of 20 km/h (12 mph).
A dash (-) or pressure value will display in
the DIC. See Driver Information Center (DIC)
(Base Level) 0126 or Driver Information Center (DIC) (Uplevel)
0
127. A warning message displays in the
DIC if a problem occurs during the relearn
process.
Trailer Tire Pressure Monitoring
Operation
If equipped, the Trailer Tire Pressure
Monitoring System (TTPMS) is designed to
monitor the pressure of the trailer tires and
warn the driver when a low pressure
condition exists. TTPMS sensors for four tires
are provided. The system can accommodate
a trailer with up to six tires if additional
sensors are purchased from the dealer. Also,
the system can be paired with up to five
individual trailers.
Prior to use, the vehicle must learn the
sensors by following the learning process.
See Trailering App 0318.
Contact your trailer service center or tire
service center to have the pressure sensors
installed inside the trailer tires. The
technician should insert the sensor stem
through the hole in the trailer wheel. When
the sensor is correctly positioned, the nut on
the sensor stem should be tightened to
8Y (6 lb ft). When mounting the trailer
tire onto the trailer wheel be careful not to
damage the sensor.
The Trailering App can be used to view the
tire pressures after the recommended trailer
tire pressures have been entered. Refer to
the trailer tire placard on the trailer or the
trailer tire sidewall for the recommended
tire pressure.

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico/Paraguay-16515119) - 2023 - CRC - 6/2/22
Vehicle Care 381
The system is compatible with trailer tires
that have placard pressure values from 103 -
689 kpa (15 - 100 psi). The hole in the wheel
for the tire stem must be either 11.43 mm
(0.453 in) or 15.88 mm (0.625 in) in
diameter. Use of the pressure sensors on a
wheel with a different stem hole size could
result in loss of air from the tire.
If a low trailer tire pressure condition is
detected, the TTPMS displays a warning
message on the DIC. If the warning message
is displayed, stop as soon as possible and
inflate the tires to the recommended
pressure shown on the tire placard on the
trailer.
In addition, the TTPMS monitors the
temperature of the trailer tires. If the
system detects a high temperature on one
or more of the trailer tires, a warning
message will be displayed on the DIC. If this
warning message is displayed, stop as soon
as possible, and inspect the overheated
trailer tire. Common causes for high trailer
tire temperature are underinflation,
overloading, or tire damage.TTPMS Malfunction Message
The TTPMS will not function properly if one
or more of the trailer tire sensors are
missing or inoperable. If the system detects
a malfunction, a DIC message indicates that
the system requires service. Some of the
conditions that can cause the service
message to occur are:
.One of the trailer tires has been replaced
with the spare tire which does not have a
learned TTPMS sensor. The DIC message
should turn off after the pressure sensor
is installed in the tire, and the learning
process is performed successfully. See
"TTPMS Sensor Learning Process" under
Trailering App0318.
.The TTPMS sensor learning process was
not done or not completed successfully.
The DIC message should go off after
successfully completing the sensor
learning process. See "TTPMS Sensor
Learning Process" under Trailering App
0 318.
.One or more TTPMS sensors are missing
or damaged. The DIC message should go
off when the TTPMS sensors are installed
and the sensor learning process is performed successfully. See "TTPMS
Sensor Learning Process" under
Trailering
App 0318.
.Operating electronic devices or being near
facilities using radio wave frequencies
similar to the TTPMS could cause
interference to the TTPMS which could
cause loss of signal reception from the
sensor.
.If the system does not receive the signal
from an individual sensor, an error
message may not occur until the vehicle
has been driver for a period of time.
If the TTPMS is not functioning properly, it
cannot detect or signal a low tire condition.
See your dealer for service if the DIC
message comes on and stays on when the
trailer tire pressures have been checked and
determined to be correct.
Tire Inspection
We recommend that the tires, including
the spare tire, if the vehicle has one, be
inspected for signs of wear or damage
at least once a month.
Replace the tire if:
.The indicators at three or more
places around the tire can be seen.

Chevrolet Silverado 1500 Owner Manual (GMNA-Localizing-U.S./Canada/
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Vehicle Care 385
Different Size Tires and Wheels
If wheels or tires are installed that are a
different size than the original equipment
wheels and tires, vehicle performance,
including its braking, ride and handling
characteristics, stability, and resistance to
rollover may be affected. If the vehicle has
electronic systems such as antilock brakes,
rollover airbags, traction control, electronic
stability control, or All-Wheel Drive, the
performance of these systems can also be
affected.
{Warning
If different sized wheels are used, there
may not be an acceptable level of
performance and safety if tires not
recommended for those wheels are
selected. This increases the chance of a
crash and serious injury. Only use GM
specific wheel and tire systems developed
for the vehicle, and have them properly
installed by a GM certified technician.
See Buying New Tires 0383 and
Accessories and Modifications 0332.
Uniform Tire Quality Grading
The following information relates to the
system developed by the United States
National Highway Traffic Safety
Administration (NHTSA), which grades
tires by treadwear, traction, and
temperature performance. This applies
only to vehicles sold in the United
States. The grades are molded on the
sidewalls of most passenger car tires.
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 controlled
conditions 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.