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DRIVING AND OPERATING 279
Trailer Wiring Harness
Basic Trailer Wiring
The trailer wiring harness is located at
the rear of the vehicle and is tied to
the vehicle's frame. The harness
connector can be plugged into a
trailer connector available through
your dealer.
Trailer Lamps
Always check all trailer lamps are
working at the beginning of each trip,
and periodically on longer trips.
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 Sway Control (TSC)
Vehicles with StabiliTrak/Electronic
Stability Control (ESC) have a Trailer
Sway Control (TSC) feature. Trailersway is unintended side-to-side
motion of a trailer while towing. If the
vehicle is towing a trailer and the TSC
detects that sway is increasing, the
vehicle brakes are selectively applied
at each wheel, to help reduce
excessive trailer sway. If equipped with
the Integrated Trailer Brake Control
(ITBC) system, and the trailer has an
electric brake system, StabiliTrak/ESC
may also apply the trailer brakes.
If TSC is enabled, the Traction Control
System (TCS)/StabiliTrak/ESC warning
light will flash on the instrument
cluster. Reduce vehicle speed by
gradually removing your foot from the
accelerator. If trailer sway continues,
StabiliTrak/ESC can reduce engine
torque to help slow the vehicle. TSC
will not function if StabiliTrak/ESC is
turned off. See
Traction Control/
Electronic Stability Control 0235.
{Warning
Trailer sway can result in a crash
and in serious injury or death, even
if the vehicle is equipped with TSC.
If the trailer begins to sway, reduce
vehicle speed by gradually removing
your foot from the accelerator. Then
pull over to check the trailer and
vehicle to help correct possible
causes, including an improperly or
overloaded trailer, unrestrained
cargo, improper trailer hitch
configuration, or improperly
inflated or incorrect vehicle or
trailer tires. See Towing Equipment
0 277 for trailer ratings and hitch
setup recommendations.
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.
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VEHICLE CARE 281
Vehicle Care
General Information
General Information . . . . . . . . . . . . . 282
California Proposition65 Warning . . . . . . . . . . . . . . . . . . . . . 282
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . 282
Accessories and Modifications . . . . . . . . . . . . . . . . . . . 283
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . . . . . . 283
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . . . . . . 285
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . 286
Engine Oil Life System . . . . . . . . . . . 288
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289
Engine Air Filter Life System . . . . 289
Engine Air Cleaner/Filter . . . . . . . . . 290
Cooling System . . . . . . . . . . . . . . . . . . . 291
Engine Overheating . . . . . . . . . . . . . . 294
Washer Fluid . . . . . . . . . . . . . . . . . . . . . 295
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . 296
Battery - North America . . . . . . . . . 297
All-Wheel Drive . . . . . . . . . . . . . . . . . . 298 Park Brake and P (Park)
Mechanism Check . . . . . . . . . . . . . . 298
Wiper Blade Replacement . . . . . . . 299
Windshield Replacement . . . . . . . . 300
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . 300
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . 301
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . 301
LED Lighting . . . . . . . . . . . . . . . . . . . . . 301
Back-Up Lamps . . . . . . . . . . . . . . . . . . . 302
Electrical System
Electrical System Overload . . . . . . 302
Fuses and Circuit Breakers . . . . . . 303
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
Instrument Panel Fuse Block . . . . 306
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308
All-Season Tires . . . . . . . . . . . . . . . . . . 309
Winter Tires . . . . . . . . . . . . . . . . . . . . . . 310
Summer Tires . . . . . . . . . . . . . . . . . . . . 310
Tire Sidewall Labeling . . . . . . . . . . . 310
Tire Designations . . . . . . . . . . . . . . . . . 312
Tire Terminology and Definitions . . . . . . . . . . . . . . . . . . . . . . 313
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . 316 Tire Pressure for High-Speed
Operation . . . . . . . . . . . . . . . . . . . . . . . . 317
Tire Pressure Monitor System . . . 318
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . . . . . . 319
Tire Inspection . . . . . . . . . . . . . . . . . . . 322
Tire Rotation . . . . . . . . . . . . . . . . . . . . . 323
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324
Buying New Tires . . . . . . . . . . . . . . . . 325
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . . . . . 326
Uniform Tire Quality Grading . . . 326
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . . . . . . 328
Wheel Replacement . . . . . . . . . . . . . . 328
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . 328
If a Tire Goes Flat . . . . . . . . . . . . . . . . 329
Tire Sealant and Compressor Kit . . . . . . . . . . . . . . . . . 331
Storing the Tire Sealant and Compressor Kit . . . . . . . . . . . . . . . . . 336
Tire Changing . . . . . . . . . . . . . . . . . . . . . 337
Compact Spare Tire . . . . . . . . . . . . . . 341
Jump Starting
Jump Starting - North America . . . . . . . . . . . . . . . . . . . . . . . . . 342
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Warning (Continued)
.Overloading the tires can
cause overheating as a result
of too much flexing. There
could be a blowout and a
serious crash. SeeVehicle
Load Limits 0215.
.Underinflated tires pose the
same danger as overloaded
tires. The resulting crash
could cause serious injury.
Check all tires frequently to
maintain the recommended
pressure. Tire pressure should
be checked when the tires
are cold.
.Overinflated tires are more
likely to be cut, punctured,
or broken by a sudden impact
— such as when hitting a
pothole. Keep tires at the
recommended pressure.
(Continued)
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 the 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.
See Tire Pressure for High-Speed
Operation 0317 for inflation
pressure adjustment for
high-speed driving.
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. Original equipment
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 Tires 0310.
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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
0 341 and
If a Tire Goes Flat 0329. (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 0316.
(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 example shows a typical
passenger vehicle tire size.
Passenger (P-Metric) Tire
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314 VEHICLE CARE
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 Identification Number
(TIN), an alphanumeric designator
which can also identify the tire
manufacturer, production plant,
brand, and date of production.
GVWR
:Gross Vehicle Weight
Rating. See Vehicle Load Limits
0 215.
GAWR FRT
:Gross Axle Weight
Rating for the front axle. See
Vehicle Load Limits 0215.
GAWR RR
:Gross Axle Weight
Rating for the rear axle. See
Vehicle Load Limits 0215. 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.
Load Index
:An assigned number
ranging from 1 to 279 that
corresponds to the load carrying
capacity of a tire.
Maximum Inf lation Pressure
:
The maximum air pressure to
which a cold tire can be inflated.
The maximum air pressure is
molded onto the sidewall.
Maximum Load Rating
:The load
rating for a tire at the maximum
permissible inflation pressure for
that tire. Maximum Loaded Vehicle
Weight
:The sum of curb weight,
accessory weight, vehicle capacity
weight, and production options
weight.
Normal Occupant Weight
:The
number of occupants a vehicle is
designed to seat multiplied by
68 kg (150 lb). See Vehicle Load
Limits 0215.
Occupant Distribution
:
Designated seating positions.
Outward Facing Sidewall
:The
side of an asymmetrical tire that
has a particular side that faces
outward when mounted on a
vehicle. The side of the tire that
contains a whitewall, bears white
lettering, or bears manufacturer,
brand, and/or model name
molding that is higher or deeper
than the same moldings on the
other sidewall of the tire.
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Passenger (P-Metric) Tire:A tire
used on passenger cars and some
light duty trucks and
multipurpose vehicles.
Recommended Inf lation
Pressure
:Vehicle manufacturer's
recommended tire inflation
pressure as shown on the tire
placard. See Tire Pressure 0316
and
Vehicle Load Limits 0215.
Radial Ply Tire
:A pneumatic tire
in which the ply cords that extend
to the beads are laid at 90 degrees
to the centerline of the tread.
Rim
:A metal support for a tire
and upon which the tire beads are
seated.
Sidewall
:The portion of a tire
between the tread and the bead.
Speed Rating
:An alphanumeric
code assigned to a tire indicating
the maximum speed at which a
tire can operate. Traction
:The friction between
the tire and the road surface. The
amount of grip provided.
Tread
:The portion of a tire that
comes into contact with the road.
Treadwear Indicators
:Narrow
bands, sometimes called wear
bars, that show across the tread of
a tire when only 1.6 mm (1/16 in)
of tread remains. See When It Is
Time for New Tires 0324.
UTQGS (Uniform Tire Quality
Grading Standards)
:A tire
information system that provides
consumers with ratings for a tire's
traction, temperature, and
treadwear. Ratings are determined
by tire manufacturers using
government testing procedures.
The ratings are molded into the
sidewall of the tire. See Uniform
Tire Quality Grading 0326. Vehicle Capacity Weight
:The
number of designated seating
positions multiplied by
68 kg (150 lb) plus the rated cargo
load. See Vehicle Load Limits 0215.
Vehicle Maximum Load on the
Tire
:Load on an individual tire
due to curb weight, accessory
weight, occupant weight, and
cargo weight.
Vehicle Placard
:A label
permanently attached to a vehicle
showing the vehicle capacity
weight and the original equipment
tire size and recommended
inflation pressure. See “Tire and
Loading Information Label” under
Vehicle Load Limits 0215.
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Tire Pressure
Tires need the correct amount of
air pressure to operate effectively.
{Warning
Neither tire underinflation nor
overinflation is good.
Underinflated tires, or tires that
do not have enough air, can
result in:
.Tire overloading and
overheating, which could lead
to a blowout.
.Premature or irregular wear.
.Poor handling.
.Reduced fuel economy.
Overinflated tires, or tires that
have too much air, can result in:
.Unusual wear.
.Poor handling.
(Continued)
Warning (Continued)
.Rough ride.
.Needless damage from road
hazards.
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. See Vehicle Load Limits
0 215.
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 compact
spare cold tire pressure should be
at 420 kPa (60 psi). See
Compact
Spare Tire 0341.
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).
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VEHICLE CARE 317
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. 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
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 tire sizes listed in the
High Speed Operation Inflation
Pressures table require inflation
pressure adjustment when driving the
vehicle at speeds of 160 km/h
(100 mph) or higher. Set the cold tire
inflation pressure to the
corresponding value in the table for
the tire size on the vehicle.