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When you install dual wheels, be sure that vent holes in
the inner and outer wheels on each side are lined up.
After the tires have been rotated, adjust the front
and rear in¯ation pressures as shown on the
Certi®cation/Tire label. Make certain that all wheel nuts
are properly tightened. See ªWheel Nut Torqueº
under
Capacities and Speci®cations on page 5-97.
{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 an accident. 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. See ªChanging a Flat
Tireº in the Index.
When It Is Time for New Tires
One way to tell when it's
time for new tires is to
check the treadwear
indicators, which will
appear when your tires
have only 1/16 inch
(1.6 mm) or less of tread
remaining. Some
commercial truck tires may
not have treadwear
indicators.
You need a new tire if any of the following statements
are true:
·You can see the indicators at three or more places
around the tire.
·You can see cord or fabric showing through the
tire's rubber.
·The tread or sidewall is cracked, cut or snagged
deep enough to show cord or fabric.
·The tire has a bump, bulge or split.
·The tire has a puncture, cut or other damage that
can't be repaired well because of the size or
location of the damage.
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If a Tire Goes Flat
It's unusual for a tire to ªblowoutº while you're driving,
especially if you maintain your tires properly. If air goes
out of a tire, it's much more likely to leak out slowly.
But if you should ever have a ªblowout,º here are a few
tips about what to expect and what to do:
If a front tire fails, the ¯at tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel ®rmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you'd use
in a skid. In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop, well off the road if possible.{CAUTION:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without
the appropriate safety equipment and training.
The jack provided with your vehicle is
designed only for changing a ¯at tire. If it is
used for anything else, you or others could be
badly injured or killed if the vehicle slips off
the jack. Use the jack provided with your
vehicle only for changing a ¯at tire.
If a tire goes ¯at, the next part shows how to use your
jacking equipment to change a ¯at tire safely.
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Turn the ratchet counterclockwise to lower the spare tire
to the ground. If the spare tire does not lower to the
ground, the secondary latch is engaged causing the tire
not to lower. See ªSecondary Latch Systemº later in
this section.When the tire has been lowered, pull the tire toward you
so you can reach the tire retainer and pull it up
through the wheel opening.
If you have a vehicle which was completed from a cab
and chassis, refer to the information from the body
supplier/installer.
The spare tire is a full-size tire, like the other tires on
your vehicle.
Notice:To help avoid vehicle damage, do not drive
the vehicle before the cable is restored.
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Secondary Latch System
Your vehicle has an underbody mounted tire hoist
assembly equipped with a secondary latch system. It's
designed to stop the spare tire from suddenly falling
off your vehicle if the cable holding the spare tire
is damaged. For the secondary latch to work, the tire
must be stowed with the valve stem pointing down.
See ªStoring the Spare Tire and Toolsº later in
this section for instructions on storing the spare tire
correctly.
{CAUTION:
Before beginning this procedure read all the
instructions. Failure to read and follow the
instructions could damage the hoist assembly
and you and others could get hurt. Read and
follow the instructions listed below.
To release the spare tire from the secondary latch, do
the following:
{CAUTION:
Someone standing too close during the
procedure could be injured by the jack. If the
spare tire does not slide off the jack
completely, make sure no one is behind you or
on either side of you as you pull the jack out
from the spare.
1. Check under the vehicle to see if the cable end is
visible.
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6. Remove any rust or dirt
from the wheel bolts,
mounting surfaces
and spare wheel.
{CAUTION:
Rust or dirt on the wheel, or on the parts to
which it is fastened, can make the wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
the 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 nuts. If
you do, the nuts might come loose. Your wheel
could fall off, causing a serious accident.
7. Put the wheel nuts
back on with the
rounded end of the
nuts toward the wheel.
Tighten each wheel
nut by hand until
the wheel is held
against the hub.
8. Lower the vehicle by turning the jack handle
counterclockwise. Lower the jack completely.
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3. Pull the wheel toward the rear of the vehicle,
keeping the cable tight.4. Attach the ratchet, with the UP side facing you, to
the wheel wrench.
5. Put the ¯at end of the wheel wrench on an angle
through the hole in the rear door frame, above the
bumper.
6. Raise the tire fully against the underside of the
vehicle. Continue turning the ratchet until the tire
is secure and the cable is tight. The spare tire hoist
cannot be overtightened.
7. Make sure the tire is stored securely. Push, pull,
and then try to rotate or turn the tire. If the tire
moves, use the ratchet to tighten the cable.
You will hear two²clicksº when the tire is up all
the way.
Return the jacking equipment to the proper location.
Secure the items and replace the jack cover.
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Here are some cleaning tips:
·Always read the instructions on the cleaner label.
·Clean up stains as soon as you can ± before
they set.
·Carefully scrape off any excess stain.
·Use a clean cloth or sponge, and change to a clean
area often. A soft brush may be used if stains are
stubborn.
·If a ring forms on fabric after spot cleaning, clean
the entire area immediately or it will set.
Using Cleaner on Fabric
1. Vacuum and brush the area to remove any
loose dirt.
2. Always clean a whole trim panel or section. Mask
surrounding trim along stitch or welt lines.
3. Follow the directions on the container label.
4. Apply cleaner with a clean sponge. Don't saturate
the material and don't rub it roughly.
5. As soon as you've cleaned the section, use a
sponge to remove any excess cleaner.
6. Wipe cleaned area with a clean, water-dampened
towel or cloth.
7. Wipe with a clean cloth and let dry.
Special Fabric Cleaning Problems
Stains caused by such things as catsup, coffee (black),
egg, fruit, fruit juice, milk, soft drinks, vomit, urine
and blood can be removed as follows:
1. Carefully scrape off excess stain, then sponge the
soiled area with cool water.
2. If a stain remains, follow the cleaner instructions
described earlier.
3. If an odor lingers after cleaning vomit or urine,
treat the area with a water/baking soda solution:
1 teaspoon (5 ml) of baking soda to 1 cup (250 ml)
of lukewarm water.
4. Let dry.
Stains caused by candy, ice cream, mayonnaise, chili
sauce and unknown stains can be removed as follows:
1. Carefully scrape off excess stain.
2. Clean with cool water and allow to dry completely.
3. If a stain remains, follow the cleaner instructions
described earlier.
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Care of Safety Belts
Keep belts clean and dry.
{CAUTION:
Do not bleach or dye safety belts. If you do, it
may severely weaken them. In a crash, they
might not be able to provide adequate
protection. Clean safety belts only with mild
soap and lukewarm water.
Weatherstrips
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth at least every
six months. During very cold, damp weather more
frequent application may be required. See
Part D: Recommended Fluids and Lubricants on
page 6-18.
Cleaning the Outside of Your
Vehicle
The paint ®nish on your vehicle provides beauty, depth
of color, gloss retention and durability.
Washing Your Vehicle
The best way to preserve your vehicle's ®nish is to keep
it clean by washing it often with lukewarm or cold
water.
Don't wash your vehicle in the direct rays of the sun.
Use a car washing soap. Don't use strong soaps
or chemical detergents. Be sure to rinse the vehicle
well, removing all soap residue completely. You can get
GM-approved cleaning products from your dealer.
See
Vehicle Care/Appearance Materials on page 5-88.
Don't use cleaning agents that are petroleum based,
or that contain acid or abrasives. All cleaning agents
should be ¯ushed promptly and not allowed to dry on the
surface, or they could stain. Dry the ®nish with a soft,
clean chamois or an all-cotton towel to avoid surface
scratches and water spotting.
High pressure car washes may cause water to enter
your vehicle.
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