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Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place. Turn on the hazard
warning flashers. SeeHazard Warning Flashers
on page 3-6.
{CAUTION:
Changing a tire can be dangerous. The vehicle
can slip off the jack and roll over or fall on you or
other people. You and they could be badly injured
or even killed. Find a level place to change your
tire. To help prevent the vehicle from moving:
1. Set the parking brake firmly.
2. Put the shift lever in P (Park).
3. Turn off the engine and do not restart while
the vehicle is raised.
4. Do not allow passengers to remain in the
vehicle.
CAUTION: (Continued)
CAUTION: (Continued)
To be even more certain the vehicle will not move,
you should put blocks at the front and rear of the
tire farthest away from the one being changed.
That would be the tire, on the other side, at the
opposite end of the vehicle.
When the vehicle has a flat tire (B), use the following
example as a guide to assist you in the placement
of wheel blocks (A).
A. Wheel Block
B. Flat Tire
The following information explains how to use the jack
and change a tire.
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1. Assemble the wheel wrench (G) to one or two of
the jack handle extensions and the hoist extension.
Insert the hoist extension end through the hole
in the rear bumper.
2. Be sure the hoist extension end connects to the
hoist shaft (E). The chiseled end of the extension
is used to lower the spare tire.
3. Turn the wheel wrench counterclockwise to lower
the spare tire to the ground. Continue to turn the
wheel wrench until the spare tire can be pulled out
from under the vehicle.
If the spare tire does not lower to the ground, the
secondary latch is engaged causing the tire not to
lower. SeeSecondary Latch System on page 5-91.4. 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
body supplier/installer.
The spare tire is a full-size tire, like the other tires
on the vehicle.
5. Put the spare tire near the flat tire.
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Removing the Flat Tire and
Installing the Spare Tire
If your vehicle has plastic wheel nut caps, loosen
them by turning the wheel wrench counterclockwise.
The wheel nut caps are designed to remain with
the center cap. Remove the center cap.
If the wheel has a smooth center piece, place the chisel
end of the wheel wrench in the slot on the wheel and
gently pry it out.
1. Do a safety check before proceeding. SeeChanging
a Flat Tire on page 5-80for more information.
2. Loosen all the wheel nuts with the wheel wrench.
Do not remove them yet.
3. Assemble the jack and tools:Front Flat:Assemble the jack (A) together with the
jack handle (B), 1 or 2 jack handle extensions (D)
and the wheel wrench (E).
Rear Flat:Assemble the jack (A) together with
the jack handle (B), 2 jack handle extensions (D),
and the wheel wrench (E).
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{CAUTION:
Getting under a vehicle when it is jacked up is
dangerous. If the vehicle slips off the jack you
could be badly injured or killed. Never get under
a vehicle when it is supported only by a jack.
{CAUTION:
Raising your vehicle with the jack improperly
positioned can damage the vehicle and even
make the vehicle fall. To help avoid personal injury
and vehicle damage, be sure to fit the jack lift
head into the proper location before raising the
vehicle.5. Raise the vehicle by turning the wheel wrench
clockwise. Raise the vehicle far enough off the
ground so there is enough room for the spare
tire to fit.
6. Remove all the
wheel nuts.
7. Take flat tire off of the mounting surface.
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9. 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.
10. Lower the vehicle by turning the jack handle
counterclockwise. Lower the jack completely.
{CAUTION:
Wheel nuts that are not tight can work loose. If all
the nuts on a wheel come off, the wheel can come
off the vehicle, causing a crash. All wheel nuts
must be properly tightened. Follow the rules in
this section to be sure they are.
{CAUTION:
If wheel studs are damaged, they can break. If all
the studs on a wheel broke, the wheel could come
off and cause a crash. If any stud is damaged
because of a loose-running wheel, it could be that
all of the studs are damaged. To be sure, replace
all studs on the wheel. If the stud holes in a wheel
have become larger, the wheel could collapse in
operation. Replace any wheel if its stud holes have
become larger or distorted in any way. Inspect hubs
and hub-piloted wheels for damage. Because of
loose running wheels, piloting pad damage may
occur and require replacement of the entire hub,
for proper centering of the wheels. When replacing
studs, hubs, wheel nuts or wheels, be sure to use
GM original equipment parts.
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{CAUTION:
Incorrect or improperly tightened wheel nuts can
cause the wheel to come loose and even come off.
This could lead to a crash. If you have to replace
them, be sure to get new original equipment wheel
nuts. Stop somewhere as soon as you can and
have the nuts tightened with a torque wrench to the
proper torque specification. SeeCapacities and
Specifications on page 5-110for wheel nut torque
specification.
Notice:Improperly tightened wheel nuts can
lead to brake pulsation and rotor damage. To avoid
expensive brake repairs, evenly tighten the wheel
nuts in the proper sequence and to the proper torque
speci cation. SeeCapacities and Specifications on
page 5-110for the wheel nut torque speci cation.11. Use the wheel wrench to tighten the nuts firmly.
Turn the wheel wrench clockwise and in a
crisscross sequence as shown.
12. Put the wheel cover or the center cap and plastic
wheel nut caps back on. Remove any wheel
blocks.
Have a technician check the wheel nut tightness
of all wheels with a torque wrench after the first
100 miles (160 km) and then 1,000 miles (1600 km)
after that. Repeat this service whenever you have
a tire removed or serviced. SeeCapacities and
Specifications on page 5-110for more information.
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Secondary Latch System
Your vehicle has an underbody-mounted tire hoist
assembly equipped with a secondary latch system.
It is designed to stop the spare tire from suddenly
falling off the 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.
SeeStoring a Flat or Spare Tire and Tools on
page 5-94for 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 next.To release the spare tire from the secondary latch:
{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 under spare.
1. Check under the
vehicle to see if the
cable end is visible.
If the cable is not
visible, start this
procedure at Step 6.
2. Turn the hoist extension counterclockwise until
approximately 6 inches (15 cm) of cable is exposed.
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3. Attach the jack handle/jack handle extension and
wheel wrench to the jack.4. Place the jack under the vehicle, ahead of the rear
bumper. Position the center lift point of the jack
under the center of the spare tire and turn the
handle clockwise to raise the jack until it lifts
the secondary latch spring.
5-92