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286 DRIVING AND OPERATING
Towing Equipment
Hitches
Always use the correct hitch
equipment for your vehicle.
Crosswinds, large trucks going by, and
rough roads can affect the trailer and
the hitch.
Never attach rental hitches or other
bumper-type hitches. Only use
frame-mounted hitches that do not
attach to the bumper.
Always seal any holes in your vehicle
if the trailer hitch removed. If not
sealed, dirt, water, and carbon
monoxide (CO) from the exhaust may
enter your vehicle. SeeEngine Exhaust
0 209.
Tires
.
Do not tow a trailer while using a
compact spare tire on the vehicle.
. Tires must be properly inflated to
support loads while towing a
trailer. See Tires0339 for
instructions on proper tire
inflation.
Safety Chains
Always attach chains between the
vehicle and the trailer, and attach the
chains to the holes on the trailer hitch
platform. Instructions about safety
chains may be provided by the hitch
manufacturer or by the trailer
manufacturer.
Cross the safety chains under the
tongue of the trailer to help prevent
the tongue from contacting the road if
it becomes separated from the hitch.
Always leave just enough slack so the
combination can turn. Never allow
safety chains to drag on the ground.
Trailer Brakes
State or local regulations may require
trailers to have their own braking
system if the loaded weight of the
trailer exceeds certain minimums that
can vary from state to state. Read and
follow the instructions for the trailer
brakes so they are installed, adjusted,
and maintained properly. Never
attempt to tap into your vehicle's
hydraulic brake system. If you do, both the vehicle anti-lock brakes and
the trailer brakes may not function,
which could result in a crash.
Turn Signals When Towing a
Trailer
When properly connected, the trailer
turn signals will illuminate to indicate
the vehicle is turning, changing lanes,
or stopping. When towing a trailer,
the arrows on the instrument cluster
will illuminate even if the trailer is not
properly connected or the bulbs are
burned out.
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.

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288 VEHICLE CARE
Vehicle Care
General Information
General Information . . . . . . . . . . . . . 289
California Proposition65 Warning . . . . . . . . . . . . . . . . . . . . . 289
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . 290
Accessories and Modifications . . . . . . . . . . . . . . . . . . . 290
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . . . . . . 290
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . . . . . . 292
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . 299
Engine Oil Life System . . . . . . . . . . . 302
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
Engine Air Filter Life System . . . . 304
Engine Air Cleaner/Filter . . . . . . . . . 304
Cooling System . . . . . . . . . . . . . . . . . . . 307
Engine Overheating . . . . . . . . . . . . . . 312
Washer Fluid . . . . . . . . . . . . . . . . . . . . . 313
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314
Brake Pad Life System . . . . . . . . . . . 315
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . 315 Battery - North America . . . . . . . . . 316
All-Wheel Drive . . . . . . . . . . . . . . . . . . 317
Starter Switch Check . . . . . . . . . . . . . 318
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . . . . . 318
Wiper Blade Replacement . . . . . . . 319
Windshield Replacement . . . . . . . . 319
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . 320
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . . . . . 321
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . 321
LED Lighting . . . . . . . . . . . . . . . . . . . . . 321
Electrical System
Electrical System Overload . . . . . . 322
Fuses and Circuit Breakers . . . . . . 322
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
Instrument Panel Fuse Block . . . . 330
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339
All-Season Tires . . . . . . . . . . . . . . . . . . 340
Winter Tires . . . . . . . . . . . . . . . . . . . . . . 340
Low-Profile Tires . . . . . . . . . . . . . . . . . 340
Summer Tires . . . . . . . . . . . . . . . . . . . . 340
Tire Sidewall Labeling . . . . . . . . . . . 341 Tire Designations . . . . . . . . . . . . . . . . . 343
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . . . . . 344
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . 346
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . 347
Tire Pressure Monitor System . . . 348
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . . . . . . 349
Tire Inspection . . . . . . . . . . . . . . . . . . . 353
Tire Rotation . . . . . . . . . . . . . . . . . . . . . 353
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 354
Buying New Tires . . . . . . . . . . . . . . . . 355
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . . . . . 356
Uniform Tire Quality Grading . . . 357
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . . . . . . 358
Wheel Replacement . . . . . . . . . . . . . . 358
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . 359
If a Tire Goes Flat . . . . . . . . . . . . . . . . 359
Tire Changing . . . . . . . . . . . . . . . . . . . . . 361
Compact Spare Tire . . . . . . . . . . . . . . 366Jump Starting
Jump Starting - North America . . . . . . . . . . . . . . . . . . . . . . . . . 367
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . . . . . 370

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VEHICLE CARE 317
The battery is in the trunk under the
spare tire. Refer to the replacement
number shown on the original battery
label when a new 12-volt battery is
needed.
The vehicle has an Absorbed Glass
Mat (AGM) 12-volt battery.
Installation of a standard 12-volt
battery will result in reduced 12-volt
battery life.
When using a 12-volt battery charger
on the 12-volt AGM battery, some
chargers have an AGM battery setting
on the charger. If available, use the
AGM setting on the charger, to limit
charge voltage to 14.8 volts.
Stop/Start System
Vehicles equipped with a 2.0L LSY,
3.0L LGW, 3.6L LGX, or 4.2L LTA
engine are equipped with a Stop/Start
system to shut off the engine to help
conserve fuel. SeeStop/Start System
0 203.{Warning
WARNING: Battery posts,
terminals, and related accessories
contain lead and lead compounds,
chemicals known to the State of
California to cause cancer and birth
defects or other reproductive harm.
Batteries also contain other
chemicals known to the State of
California to cause cancer. WASH
HANDS AFTER HANDLING. For
more information go to
www.P65Warnings.ca.gov/
passenger-vehicle.
See California Proposition 65 Warning
0 289 and the back cover.
Vehicle Storage
{Warning
Batteries have acid that can burn
you and gas that can explode. You
can be badly hurt if you are not
careful. See Jump Starting - North
(Continued)
Warning (Continued)
America0367 for tips on working
around a battery without
getting hurt.
Infrequent Usage: Remove the 12-volt
battery black, negative (−) cable from
the battery to keep the battery from
running down.
Extended Storage: Remove the 12-volt
battery black, negative (−) cable from
the battery or use a battery trickle
charger.
Remember to reconnect the battery
when ready to drive the vehicle.
All-Wheel Drive
If the vehicle is equipped with
All-Wheel Drive (AWD), this is an
additional system that needs
lubrication.

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VEHICLE CARE 341
and compound that are optimized for
maximum dry and wet road
performance. This special tread and
compound will have decreased
performance in cold climates, and on
ice and snow. It is recommended that
winter tires be installed on the vehicle
if frequent driving at temperatures
below approximately 5 °C (40 °F) or on
ice or snow covered roads is expected.
SeeWinter Tires 0340.
Caution
High performance summer tires
have rubber compounds that lose
flexibility and may develop surface
cracks in the tread area at
temperatures below −7 °C (20 °F).
Always store high performance
summer tires indoors and at
temperatures above −7 °C (20 °F)
when not in use. If the tires have
been subjected to −7 °C (20 °F) or
(Continued)
Caution (Continued)
less, let them warm up in a heated
space to at least 5 °C (40 °F) for
24 hours or more before being
installed or driving a vehicle on
which they are installed. Do not
apply heat or blow heated air
directly on the tires. Always inspect
tires before use. See Tire Inspection
0 353.
Tire Sidewall Labeling
Useful information about a tire is
molded into its sidewall. The
examples show a typical passenger
vehicle tire and a compact spare
tire sidewall.
Passenger (P-Metric) Tire Example
(1) Tire Size:The tire size is a
combination of letters and
numbers used to define a
particular tire's width, height,
aspect ratio, construction type,
and service description. See the
“Tire Size ”illustration later in this
section.
(2) TPC Spec (Tire Performance
Criteria Specification)
:Original
equipment tires designed to GM's
specific tire performance criteria
have a TPC specification code

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342 VEHICLE CARE
molded onto the sidewall. GM's
TPC specifications meet or exceed
all federal safety guidelines.
(3) DOT (Department of
Transportation)
:The
Department of Transportation
(DOT) code indicates that the tire
is in compliance with the U.S.
Department of Transportation
Motor Vehicle Safety Standards.
DOT Tire Date of Manufacture
:
The last four digits of the TIN
indicate the tire manufactured
date. The first two digits represent
the week (01–52) and the last two
digits, the year. For example, the
third week of the year 2010 would
have a four-digit DOT date
of 0310.
(4) Tire Identification Number
(TIN)
:The letters and numbers
following the DOT (Department of
Transportation) code are the Tire
Identification Number (TIN). The
TIN shows the manufacturer and
plant code, tire size, and date the tire was manufactured. The TIN is
molded onto both sides of the tire,
although only one side may have
the date of manufacture.
(5) Tire Ply Material
:The type
of cord and number of plies in the
sidewall and under the tread.
(6) Uniform Tire Quality
Grading (UTQG)
:Tire
manufacturers are required to
grade tires based on three
performance factors: treadwear,
traction, and temperature
resistance. For more information
see Uniform Tire Quality Grading
0 357.
(7) Maximum Cold Inf lation
Load Limit
:Maximum load that
can be carried and the maximum
pressure needed to support
that load.
Compact Spare Tire Example
(1) Tire Ply Material:The type
of cord and number of plies in the
sidewall and under the tread.
(2) Temporary Use Only
:The
compact spare tire or temporary
use tire should not be driven at
speeds over 80 km/h (50 mph).
The compact spare tire is for
emergency use when a regular
road tire has lost air and gone flat.
If the vehicle has a compact spare
tire, see Compact Spare Tire 0366
and If a Tire Goes Flat 0359.

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VEHICLE CARE 343
(3) Tire Identification Number
(TIN)
:The letters and numbers
following the DOT (Department of
Transportation) code are the Tire
Identification Number (TIN). The
TIN shows the manufacturer and
plant code, tire size, and date the
tire was manufactured. The TIN is
molded onto both sides of the tire,
although only one side may have
the date of manufacture.
(4) Maximum Cold Inf lation
Load Limit
:Maximum load that
can be carried and the maximum
pressure needed to support
that load.
(5) Tire Inf lation
:The temporary
use tire or compact spare tire
should be inflated to 420 kPa
(60 psi). For more information on
tire pressure and inflation see Tire
Pressure 0346.
(6) Tire Size
:A combination of
letters and numbers define a tire's
width, height, aspect ratio,
construction type, and service description. The letter T as the
first character in the tire size
means the tire is for temporary
use only.
(7) TPC Spec (Tire Performance
Criteria Specification)
:Original
equipment tires designed to GM's
specific tire performance criteria
have a TPC specification code
molded onto the sidewall. GM's
TPC specifications meet or exceed
all federal safety guidelines.
Tire Designations
Tire Size
The following is an example of a
typical passenger vehicle tire size.
(1) Passenger (P-Metric) Tire:
The United States version of a
metric tire sizing system. The
letter P as the first character in
the tire size means a passenger
vehicle tire engineered to
standards set by the U.S. Tire and
Rim Association.
(2) Tire Width
:The three-digit
number indicates the tire section
width in millimeters from sidewall
to sidewall.
(3) Aspect Ratio
:A two-digit
number that indicates the tire
height-to-width measurements.
For example, if the tire size aspect
ratio is 60, as shown in item 3 of
the illustration, it would mean
that the tire's sidewall is
60 percent as high as it is wide.
(4) Construction Code
:A letter
code is used to indicate the type
of ply construction in the tire. The
letter R means radial ply
construction; the letter D means

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VEHICLE CARE 347
The Tire and Loading Information
label on the vehicle indicates the
original equipment tires and the
correct cold tire inflation
pressures. The recommended
pressure is the minimum air
pressure needed to support the
vehicle's maximum load carrying
capacity. SeeVehicle Load Limits
0 197.
How the vehicle is loaded affects
vehicle handling and ride comfort.
Never load the vehicle with more
weight than it was designed to
carry.
When to Check
Check the pressure of the tires
once a month or more. Do not
forget the compact spare, if the
vehicle has one. The cold compact
spare tire pressure should be at
420 kPa (60 psi). See Compact
Spare Tire 0366. How to Check
Use a good quality pocket-type
gauge to check tire pressure.
Proper tire inflation cannot be
determined by looking at the tire.
Check the tire inflation pressure
when the tires are cold, meaning
the vehicle has not been driven for
at least three hours or no more
than 1.6 km (1 mi).
Remove the valve cap from the
tire valve stem. Press the tire
gauge firmly onto the valve to get
a pressure measurement. If the
cold tire inflation pressure
matches the recommended
pressure on the Tire and Loading
Information label, no further
adjustment is necessary. If the
inflation pressure is low, add air
until the recommended pressure is
reached. If the inflation pressure
is high, press on the metal stem in
the center of the tire valve to
release air. Recheck the tire pressure with the
tire gauge.
Put the valve caps back on the
valve stems to keep out dirt and
moisture and prevent leaks. 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 for
High-Speed Operation
{Warning
Driving at high speeds, 160 km/h
(100 mph) or higher, puts additional
strain on tires. Sustained
high-speed driving causes excessive
heat buildup and can cause sudden
tire failure. This could cause a
crash, and you or others could be
killed. Some high-speed rated tires
require inflation pressure
adjustment for high-speed
(Continued)

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348 VEHICLE CARE
Warning (Continued)
operation. When speed limits and
road conditions allow the vehicle to
be driven at high speeds, make sure
the tires are rated for high-speed
operation, are in excellent
condition, and are set to the correct
cold tire inflation pressure for the
vehicle load.
Vehicles with 235/50R18 97V or 245/
45R19 98V size tires require inflation
pressure adjustment when driving the
vehicle at speeds of
160 km/h (100 mph) or higher. Set the
cold inflation pressure for all four
tires to 270 kPa (39 psi).
Vehicles with 245/40R20 95W size
tires require inflation pressure
adjustment when driving the vehicle
at speeds of 160 km/h (100 mph) or
higher. Set the cold inflation pressure
to 290 kPa (42 psi).
Vehicles with 245/40ZR20 95Y size
tires require inflation pressure
adjustment when driving the vehicle
at speeds of 160 km/h (100 mph) or higher. Set the cold inflation pressure
for the front tires to 280 kPa (41 psi)
and the rear tires to 300 kPa (44 psi).
Return the tires to the recommended
cold tire inflation pressure when
high-speed driving has ended. See
Vehicle Load Limits
0197 and
Tire Pressure 0346.
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 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.