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5-18
Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the fan is spinning slower and the clutch is
not fully engaged. This improves fuel economy and
reduces fan noise. Under heavy vehicle loading, trailer
towing and/or high outside temperatures, the fan speed
increases as the clutch more fully engages. So you may
hear an increase in fan noise. This is normal and should
not be mistaken as the transmission slipping or making
extra shifts. It is merely the cooling system functioning
properly. The fan will slow down when additional
cooling is not required and the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
If a Tire Goes Flat
It's unusual for a tire to ªblow outº 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 flat tire will create a drag that
pulls the vehicle toward that side. Take your foot off
the accelerator pedal and grip the steering wheel firmly.
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.
If a tire goes flat, the next part shows how to use your
jacking equipment to change a flat tire safely.
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5-19
Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your hazard
warning flashers.
CAUTION:
Changing a tire can cause an injury. The vehicle
can slip off the jack and roll over you or other
people. You and they could be badly injured.
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 PARK (P).
3. Be sure the transfer case is in a drive
gear
-- not in NEUTRAL.
4. Turn off the engine.
To be even more certain the vehicle won't move,
you can 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 of the
vehicle, at the opposite end.
The following steps will tell you how to use the jack and
change a tire.
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5-21
A. Hoist Assembly
B. Hoist Shaft
C. Ratchet
D. Jack HandleE. Retainer
F. Valve Stem,
Pointed Down
G. Spare TireFollow these instructions to lower the spare tire:
1. One side of the ratchet has an UP marking. The
other side has a DOWN marking. Assemble the
ratchet to the hook near the end of the jack handle
(as illustrated) with the DOWN marking facing you.
Insert the other end through the hole in the rear
bumper and into the hoist shaft.
2. Turn the ratchet counterclockwise to lower the
spare tire to the ground. Continue to turn the
ratchet until the spare tire can be pulled out from
under the vehicle.
3. When the tire has been lowered, tilt the retainer at
the end of the cable so it can be pulled up through
the wheel opening.
4. Put the spare tire near the flat tire.
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The tools you'll be using include the jack (A), the jack
handle extension (B), the jack handle (C), the wheel
wrench (D) and the ratchet (E).
The jack handle extension is used if the flat tire is on the
rear of the vehicle.Attach the jack handle (and jack handle extension,
if needed) to the jack.
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To access the lug nuts, place the wheel wrench in the
slot on the wheel and gently pry off the center piece to
remove it.
Removing the Flat Tire and Installing the
Spare Tire
1. Use the ratchet and wheel wrench to loosen all the
wheel nuts. Turn the wheel wrench counterclockwise,
with DOWN facing you, to loosen the wheel nuts.
Don't remove the wheel nuts yet.
2. If the flat tire is on the rear of the vehicle, put the
jack handle extension on the jack handle.
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5-25
3. Position the jack under the vehicle. If the flat tire is
on the front of the vehicle, position the jack on the
frame behind the flat tire. If the flat tire is on the rear
of the vehicle, position the jack on the axle near the
flat tire between the spring and the shock absorber.
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.
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5-26
Front Position Rear Position
4. With UP on the ratchet facing you, raise the vehicle
by turning the ratchet and wheel wrench clockwise.
Raise the vehicle far enough off the ground so there
is enough room for the spare tire to fit.
5. Remove all the wheel
nuts and take off the
flat tire.
6. Remove any rust or dirt
from the wheel bolts,
mounting surfaces and
spare wheel.
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5-29
CAUTION:
Incorrect wheel nuts or improperly tightened
wheel nuts can cause the wheel to become loose
and even come off. This could lead to an accident.
Be sure to use the correct wheel nuts. If you have
to replace them, be sure to get new GM original
equipment wheel nuts.
Stop somewhere as soon as you can and have
the nuts tightened with a torque wrench to
140 lb
-ft (190 N´m)
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 specification.
Storing a Flat or Spare Tire and Tools
CAUTION:
Storing a jack, a tire or other equipment in the
passenger compartment of the vehicle could
cause injury. In a sudden stop or collision, loose
equipment could strike someone. Store all these
in the proper place.
Store the flat tire where the spare tire is stored.
Put the tools into the storage box and close it tightly. Fit
the storage box on the bracket with the bolt through the
box. Put the jack onto the box. Be sure the jack is stored
as shown in the following illustrations. The jack handle
attachment point is circled in the following illustrations
to show the direction the jack should face when it is
stored properly. Secure the emergency gloves, if your
vehicle has them, to the jack using the provided strap.
Slide the retainer over the bolt onto the jack and put the
wing nut on it. Turn the nut clockwise until it is tight
against the retainer.
Replace the jack storage cover by simply reversing the
removal procedure described earlier.