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If parking the rig on a hill:
1. Press the brake pedal, but do not shift into P (Park)
yet. 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
brake pedal until the chocks absorb the load.
4. Reapply the brake pedal. Then apply the parking
brake and shift the transmission into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal while you:
•start the engine,
•shift into a gear, and
•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. SeeScheduled Maintenance on page 7-3for more
information. Things that are especially important in trailer
operation are automatic transmission fluid, engine oil,
belts, cooling system and brake system. It is a good idea
to inspect these before and during 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. SeeEngine Overheating
on page 6-35.
Changing a Tire When Trailer Towing
If the vehicle gets a flat tire while towing a trailer,
be sure to secure the trailer and disconnect it from
the vehicle before changing the tire.
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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.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset, and be mounted
the same way as the one it replaces.
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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.
SeeChanging a Flat Tire on page 6-90for 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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8. Remove all of the
wheel nuts.
9. Remove the flat tire.10. Remove any rust or dirt
from the wheel bolts,
mounting surfaces,
and spare wheel.
{WARNING:
Rust or dirt on a wheel, or on the parts to which it is
fastened, can make wheel nuts become loose after
time. The wheel could come off and cause an
accident. When changing a wheel, remove any rust
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 6-90.
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11. Install the compact spare tire.
12. Put the wheel nuts back on with the rounded end of
the nuts toward the wheel. Tighten each nut by
hand until the wheel is held against the hub.
{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.
13. Lower the vehicle by turning the wheel wrench
counterclockwise. Lower the jack completely.
6-97