2008 CADILLAC XLR brake

Tire Terminology and Denitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of the
tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
Aspect Ratio
:The relationship of a tire’s height
to its width.
Belt
:A rubber coated layer of cords that is located
between the plies and the tread. Cords may be
made from steel or other reinforcing materials.
Bead
:The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.
Cold Tire Pressure
:The amount of air pressure in
a tire, measured in pounds per square inch (psi) or
kilopascals (kPa) before a tire has built up heat
from driving. SeeInflation - Tire Pressure on
page 6-60.Curb Weight
:The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant,
but without passengers and cargo.
DOT Markings
:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identication Number (TIN),
an alphanumeric designator which can also identify
the tire manufacturer, production plant, brand,
and date of production.
GVWR
:Gross Vehicle Weight Rating. SeeLoading
Your Vehicle on page 5-22.
GAWR FRT
:Gross Axle Weight Rating for the
front axle. SeeLoading Your Vehicle on page 5-22.
GAWR RR
:Gross Axle Weight Rating for the rear
axle. SeeLoading Your Vehicle on page 5-22.
Intended Outboard Sidewall
:The side of
an asymmetrical tire, that must always face
outward when mounted on a vehicle.
Kilopascal (kPa)
:The metric unit for air pressure.
Light Truck (LT-Metric) Tire
:A tire used on
light duty trucks and some multipurpose passenger
vehicles.
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Buying New Tires
GM has developed and matched specic tires for your
vehicle. The original equipment tires installed on
your vehicle, when it was new, were designed to meet
General Motors Tire Performance Criteria Specication
(TPC Spec) system rating. If you need replacement
tires, GM strongly recommends that you get tires with
the same TPC Spec rating. This way, your vehicle
will continue to have tires that are designed to give the
same performance and vehicle safety, during normal
use, as the original tires.
GM’s exclusive TPC Spec system considers over a
dozen critical specications that impact the overall
performance of your 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 an MS for
mud and snow. SeeTire Sidewall Labeling on
page 6-54, for additional information.
GM recommends replacing tires in sets of four. This is
because uniform tread depth on all tires will help
keep your vehicle performing most like it did when the
tires were new. Replacing less than a full set of tires can
affect the braking and handling performance of your
vehicle. SeeTire Inspection and Rotation on page 6-65.Winter tires with the same speed rating as your original
equipment tires may not be available for H, V, W, Y
and ZR speed rated tires. If you choose snow tires with
a lower speed rating, never exceed the tire’s maximum
speed capability.
{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes
(other than those originally installed on your
vehicle), brands, or types (radial and bias-belted
tires), the vehicle may not handle properly, and
you could have a crash. Using tires of different
sizes (other than those originally installed on
your vehicle), brands or types, may also cause
damage to your vehicle. Be sure to use the
correct size, brand, and type tires on all
four wheels.
6-67

{CAUTION:
If you use bias-ply tires on your vehicle,
the wheel rim anges could develop
cracks after many miles of driving. A tire
and/or wheel could fail suddenly, causing
a crash. Use only radial-ply tires with the
wheels on your vehicle.
If you must replace your vehicle’s tires with those that
do not have a TPC Spec number, make sure they
are the same size, load range, speed rating, and
construction type (radial and bias-belted tires) as your
vehicle’s original tires.
Vehicles that have a tire pressure monitoring system
could give an inaccurate low-pressure warning if
non-TPC Spec rated tires are installed on it. Non-TPC
Spec rated tires may give a low-pressure warning that is
higher or lower than the proper warning level you
would get with TPC Spec rated tires. SeeTire Pressure
Monitor System on page 6-61.
Your vehicle’s original equipment tires are listed on the
Tire and Loading Information label. SeeLoading
Your Vehicle on page 5-22, for more information about
the Tire and Loading Information label and its location
on your vehicle.
Different Size Tires and Wheels
If you add wheels or tires that are a different size than
your original equipment wheels and tires, this may
affect the way your vehicle performs, including its
braking, ride and handling characteristics, stability, and
resistance to rollover. Additionally, if your vehicle
has electronic systems such as, anti-lock brakes,
traction control, and electronic stability control, the
performance of these systems can be affected.
{CAUTION:
If you add different sized wheels, your vehicle
may not provide an acceptable level of
performance and safety if tires not
recommended for those wheels are selected.
You may increase the chance that you will
crash and suffer serious injury. Only use GM
specic wheel and tire systems developed for
your vehicle, and have them properly installed
by a GM certied technician.
SeeBuying New Tires on page 6-67andAccessories
and Modifications on page 6-3for additional information.
6-68

If you need to replace any of your wheels, wheel bolts or
wheel nuts, replace them only with new GM original
equipment parts. This way, you will be sure to have the
right wheel, wheel bolts, and wheel nuts for your vehicle.
{CAUTION:
Using the wrong replacement wheels, wheel
bolts, or wheel nuts on your vehicle can be
dangerous. It could affect the braking and
handling of your vehicle, make your tires lose
air and make you lose control. You could have
a collision in which you or others could be
injured. Always use the correct wheel, wheel
bolts, and wheel nuts for replacement.
Notice:The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance, and tire clearance to
the body and chassis.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel
could come off and cause a crash. When
you change a wheel, remove any rust or
dirt from places where the wheel attaches
to the vehicle. In an emergency, you can
use a cloth or a paper towel to do this;
but be sure to use a scraper or wire brush
later, if you need to, to get all the rust or
dirt off.
{CAUTION:
Never use oil or grease on studs or the threads
of the wheel nuts. If you do, the wheel nuts
might come loose and the wheel could fall off,
causing a crash.
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Tightening Wheel Lug Nuts
{CAUTION:
Incorrect wheel nuts or improperly tightened
wheel nuts can cause the wheel to become
loose and even come off. This could lead to a
crash. Be sure to use the correct wheel nuts.
If you have to replace them, be sure to get new
GM original equipment wheel nuts.Notice:Improperly tightened wheel nuts can lead
to brake pulsation and rotor damage. To avoid
expensive brake repairs, evenly tighten the wheel
nuts in the proper sequence and to the proper
torque specication.
Tighten the wheel lug nuts
rmly in a crisscross
sequence as shown.
6-72

Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You cannot know how it has been
used or how far it has been driven. It could fail
suddenly and cause a crash. If you have to
replace a wheel, use a new GM original
equipment wheel.
Tire Chains
{CAUTION:
Do not use tire chains. There is not enough
clearance. Tire chains used on a vehicle
without the proper amount of clearance can
cause damage to the brakes, suspension, or
other vehicle parts. The area damaged by the
tire chains could cause you to lose control of
your vehicle and you or others may be injured
in a crash. Use another type of traction device
only if its manufacturer recommends it for use
on your vehicle and tire size combination and
road conditions. Follow that manufacturer’s
instructions. To help avoid damage to your
vehicle, drive slowly, re-adjust or remove the
device if it is contacting your vehicle, and do
not spin your wheels. If you do nd traction
devices that will t, install them on the
rear tires.
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Lifting Your Vehicle
{CAUTION:
Lifting a vehicle can cause an injury.
The vehicle can slip off the jack and roll over
you or other people. You and they could be
badly injured. Find a level place to lift your
vehicle. To help prevent the vehicle from
moving:
1. Set the parking brake rmly.
2. Put an automatic transmission shift lever
in PARK (P).
3. Turn off the engine.
To be even more certain the vehicle won’t move,
you can put blocks in front of and behind the
wheels.
{CAUTION:
Getting under a vehicle when it is jacked up is
dangerous. If the vehicle slips off the jack,
you could be badly injured or killed. Never get
under a vehicle when it is supported only by
a jack.
{CAUTION:
Raising your vehicle with the jack improperly
positioned can damage the vehicle or the
vehicle may fall and cause your or others
injury.
6-74

Fuses Usage
FUSE PULLER Fuse Puller
REVERSE
LAMPReverse Lamp
RUN/CRANK Starter/Crank
PRK/BRK
SOL AParking Brake Solenoid A
REVERSE
LAMPSReverse Lamps
BTSI SOL/
COL LOCKBTSI Solenoid, Column Lock
EMPTY Not Used
EMPTY Not Used
GMLAN
DEVICESGMLAN Devices
RPA/H/C
SEAT/WPR
RELAYSRear Park Aid, Heated/Cooled
Seats, Windshield Wiper Relays
DR LOCKS Door Locks
ECM Engine Control Module
INTERIOR
LIGHTSInterior LightsFuses Usage
SDM/PSIR SW Airbags
EMPTY Not Used
ONSTAR OnStar
®
ACCA/DRIV
DR SWAdaptive Cruise Control (ACC),
Driver Door Switch
TILT/TELE
SW/MEM SEAT
MOD/TOP SWPower Tilt Wheel, Telescopic
Steering Column, Memory Seat,
Driver Seat Switch, Retractable
Hardtop Switch
IGN SW/INTR
SNSRIgnition Switch, Intrusion Sensor
STOP LAMP Stop Lamp
ISRVM/HVACInside Rearview Mirror, Climate
Control System, Column Lock,
Power Sounder
CLSTR/HUDInstrument Panel Cluster, Head-Up
Display (HUD)
RADIO/
S-BAND/VICSRadio, S-Band, CD Changer
TUTD SW/
STRG COL SWTap-Up/Tap-Down Switch
HVAC/PWR
SNDClimate Control System, Power
Sounder
6-92