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If parking the rig on a hill:1. Press the brake pedal, but do not shift into P (Park) yet for an automatic transmission, or into gear for a
manual transmission. Turn the wheels into the
curb if facing downhill or into traffic if facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply the parking brake, and then shift into P (Park) for an automatic
transmission or R (Reverse) for a manual
transmission.
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply the regular brakes and hold the pedal down while you:
•Start the engine.
•Shift into a gear.
•Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
The vehicle needs service more often when pulling a
trailer. See Scheduled Maintenance on page 7-3
for more on this. Things that are especially important in
trailer operation are automatic transmission fluid (do
not overfill), engine oil, drive belt, cooling system
and brake system.
Each of these is covered in this manual, and the Index
will help to find them quickly. When trailering, it is a good
idea to review this information before starting the trip.
Check periodically to see that all hitch nuts and bolts are
tight.
Engine Cooling When Trailer Towing
The cooling system may temporarily overheat during
severe operating conditions. See Engine Overheating on
page 6-27.
Towing a Trailer (Manual
Transmission)
Do not tow a trailer if the vehicle is equipped with a
manual transmission.
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Temperature – A, B, C
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 Vehicle Safety Standard No. 109.
Grades B and A represent higher levels of
performance on the laboratory test wheel than the
minimum required by law. It should be noted that
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.
Wheel Alignment and Tire Balance
The tires and wheels on your vehicle were aligned and
balanced carefully at the factory to give you the longest
tire life and best overall performance. Adjustments to
wheel alignment and tire balancing will not be necessary
on a regular basis. However, if you notice unusual tire
wear or your vehicle pulling to one side or the other, the
alignment might need to be checked. If you notice your
vehicle vibrating when driving on a smooth road, the tires
and wheels might need to be rebalanced. See your
dealer/retailer for proper diagnosis.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted
or corroded. If wheel nuts keep coming loose, the wheel,
wheel bolts, and wheel nuts should be replaced. If the
wheel leaks air, replace it (except some aluminum
wheels, which can sometimes be repaired). See your
dealer/retailer if any of these conditions exist.
Your dealer/retailer will know the kind of wheel
you need.
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Each new wheel should have the same load-carrying
capacity, diameter, width, offset, and be mounted
the same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts,
wheel nuts, or Tire Pressure Monitor System (TPMS)
sensors, replace them only with new GM original
equipment parts. This way, you will be sure to have the
right wheel, wheel bolts, wheel nuts, and TPMS
sensors for your vehicle.
{WARNING:
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 or tire chain
clearance to the body and chassis.
See Changing a Flat Tire on page 6-80 for more
information.
Used Replacement Wheels
{WARNING:
Putting a used wheel on the 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.
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WARNING: (Continued)
or dirt from places where the wheel attaches to
the vehicle. In an emergency, use a cloth or a
paper towel to do this; but be sure to use a
scraper or wire brush later, if needed, to get all
the rust or dirt off. SeeChanging a Flat Tire on
page 6-80.
10. Remove any rust or dirtfrom the wheel bolts,
mounting surfaces, and
spare wheel. 11. Place the compact spare tire on the wheel-mounting
surface.{WARNING:
Never use oil or grease on bolts or nuts because
the nuts might come loose. The vehicle’s wheel
could fall off, causing a crash.
12. Reinstall the wheel nuts with the rounded end of the nuts toward the wheel. Tighten each nut
clockwise by hand until the wheel is held against
the hub.
13. Lower the vehicle by turning the jack handle counterclockwise. Lower the jack completely.
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