GMC SIERRA 1997 Owners Manual

Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spi.ns 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 partially disengages.
If a Tire Goes Flat
It’s unusual for a tire to “blow out” 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 “blowout,” 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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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.
I A 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 an automatic transmission shift
lever in
PARK (P) or shift a manual
transmission to
FIRST (1) or
REVERSE (R).
3. If you have a four-wheel-drive vehicle,
be
sure the transfer case is in a drive
gear
-- not in NEUTRAL (N).
4. Turn off the engine.
CAUTION: (Continued)
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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Removing the Spare Tire and Tools
2 and 4-Door Models Extended
Cab Models
The equipment you'll need is behind the passenger's seat.
Turn the wing nut counterclockwise and remove the jack
cover, if there is one. Remove the jacking equipment.
If you have a chassis cab, refer to the information from
the body supplierhstaller for the location of your
spare tire.
You'll use the jack handle and the ratchet to remove the
underbody-mounted spare tire.
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I Lower Raise
H
/1
A. Hoist Assembly
B. Ratchet
C. Jack Handle
D. Hoist Shaft
E. Valve Stem, Pointed
Down
E Spare Tire
G. Retainer
H. Hoist Cable Follow these
instructions to lower the spare tire:
1.
2.
3.
4.
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.
Turn the ratchet
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.
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,
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).
If the flat tire is on the rear of the vehicle, you'll need
the jack handle extension also.
- .'
. . .* ::*>:.,;,: , -.... ,.
Attach the jack handle (and jack handle extension, if
needed) to the jack.
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With the UP marking on the ratchet facing you, rotate
the ratchet clockwise. That will lift the jack head a little.
If your vehicle has wheel
nut caps, use the wheel
wrench and ratchet
to remove them. Turn
the wheel wrench
counterclockwise, with
DOWN facing you, to
a remove the wheel nut caps.
Then take
off the hub cap.
If the wheel also has a trim ring, use the wheel wrench
to
pry along the edge and remove it.
If the wheel has
a smooth center piece, place the wheel
wrench in
the slot on the wheel and gently pry out.
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Removing the Flat Tire and Installing
the
Spare Tire
1 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.
3
Front
Position
Rear
Position
2. 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, position the jack on the rear axle between the
spring and the shock absorber.
I-
AC
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.
NOTICE:
Raising your vehicle with the jack improperly
positioned will damage the vehicle or may allow
the vehicle to
fall off the jack. Be sure to fit the
jack lift head into the proper location before
raising your vehicle.
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Front Position Rear Position
3. With UP on the ratchet facing you, raise the vehicle
by rotating 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.
~ 4. Remove all the wheel
nuts
and take off the
flat tire.
5. Remove any rust or dirt
from the wheel
bolts,
mounting surfaces and
spare wheel.
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I a 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.
b, 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.
6. Replace the wheel nuts
with the rounded end
of the nuts toward the
wheel. Tighten each wheel
nut by hand using
the wheel wrench until
the wheel is held against
the hub.
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Front Position Rear
Position
7. Lower the vehicle by rotating the ratchet and wheel
wrench counterclockwise. Lower the jack completely.
- 8. Tighten the nuts fdy in
a criss-cross sequence as
shown by rotating the
wheel wrench clockwise.
A 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 the
proper torque. See “Capacities and
Specifications” in the Index.
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