clutch GMC SIERRA 1993 User Guide

Here are some things you must not do if you stall, or are about to stall,
when going up a hill.
Never attempt to prevent a stall by shifting into N (Neutral) (or
depressing the clutch,
if you have a manual transmission) to “rev-up” the
engine and regain forward momentum. This won’t work. Your vehicle will
roll backwards very quickly and you could go out of control.
Instead, apply the regular brake to stop the vehicle. Then apply the parking
brake. Shift into reverse, release the parking brake, and slowl\
y back down.
Never attempt to turn around if you are about to stall when going up a
hill. If the hill is steep enough to stall your vehicle, it’s steep enough to
cause you. to roll over
if you turn around. If you can’t make it up the
hill, you must back down the hill.
Q: Suppose, after stalling, I try to back down the hill and decide I just
can’t
do it. What should I do?
A: Set the parking brake, put your transmission in P (Park) (or the manual
transmission in first gear), and turn off the engine. Leave the vehicle and \
go
get some help. Exit on the uphill side and stay clear of the\
path the vehicle
would take
if it rolled downhill. Do not shift the transfer case to N (Neutral)
when you leave the vehicle. Leave it in some gear.
Shifting the transfer case to
N (Neutral) can cause your vehicle to
roll even
if the transmission is in P (Park) (or, if you have the
manual transmission, even
if you’re in gear). This is because the N
(Neutral) position on the transfer case overrides the transmis\
sion. If
you are going to leave your vehicle, set the parking brake and shi”
the transmission to
P (Park) (or, put your manual transmission in f
gear). But do not shift the transfer case to the N (Neutral) positior
Leave the transfer case in the
2 Wheel, 4 High or 4 Low position.
1
Lriving Downhill
When off-roading takes you downhill, you’ll want to consider a number of
things:
How steep is the downhill? Will
I be able to maintain vehicle control?
What’s the surface like? Smooth? Rough? Slippery? Hard-packed \
dirt? Grave
I?
Are there hidden surface obstacles? Ruts? Logs? Boulders?
What’s at the bottom
of the hill? Is there a hidden creek bank or even a
river bottom with large rocks?
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Your Driving and the Road
If you decide you can go down a hill safely, then try to keep your vehicle
headed straight down, and use a low gear. This way, engine dr\
ag can help
your brakes and they won’t have to do
all the work. Descend slowly, keeping
your vehicle under control at all times.
CAUTION
A Heavy braking when going down a hill can cause your brakes to
overheat and fade. This could cause
loss of control and a serious ‘
accident. Apply the brakes lightly when descending a hill and use a
low gear to keep vehicle speed under
control.
Q: Are there some things I should not do when driving down a hili?
A: Yes! These are important because if you ignore them you could lose
control and have a serious accident.
When driving downhill, avoid turns that take you across the in\
cline of the
hill.
A hill that’s not too steep to drive down may be too steep to drive
across. You could
roll over if you don’t drive straight down.
Never go downhill with the transmission in N (Neutral), or with the clutch
pedal depressed in a manual shift. This is called “free-whee\
ling,” Your
brakes will have
to do all the work and could overheat and fade.
Avoid braking so hard that you lock the wheels when going downhill. If
your front wheels are locked, you can’t steer your vehicle. \
If your wheels
lock up during downhill braking, you may feel the vehicle star\
ting to slide
sideways.
To regain your direction, just ease off the brakes and steer to
keep the front of the vehicle pointing straight downhill.
Q: Am I likely to stall when going downhill?
A: It’s much more likely to happen going uphill. But if it happens going
downhill, here’s what to do.
Stop your vehicle by applying the regular brakes. Apply the pa\
rking
brake.
Shift to P (Park) (or to Neutral with the manual transmission) and, while
still braking, restart the engine.
Shift back to a low gear, release the parking brake, and drive straight
down.
If the engine won’t start, get out and get help.
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Your Driving and the Road
Power Winches
i !
If you wish to use a power winch on your vehicle, only use it \
when your
vehicle is stationary or anchored.
i
NOTICE
Use the regular brakes, set the parking brake or block the wh\
eels to keep
your vehicle from rolling.
Power rake-off (PTO)
Before using a power take-off, refer to the manufacturer’s or installer’s
instructions.
To engage a power take-off:
1. Set ths parking brake.
2. Shift the transmission into N (Neutral).
3. Hold the clutch pedal down and engage the power take-off.
*
If you are going to drive the vehicle, shift the transmission int\
o the gear
you want. Then shift the transfer case into the range you wan\
t
(if you
have four-wheel-drive), apply the regular brakes and release th\
e parking
brake.
When you release the clutch, the power take-off will start.
4. Release the clutch (and the regular brakes) as you normally \
would.
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Using a Transfer Case Mounted Power Take-Off (Manual
Transmission)
1. Set the parking brake.
2. Shift the transfer case into N (Neutral).
3. Hold the clutch pedal down. If the vehicle will remain in the same place,
4. Engage the power take-off.
shift the transmission into the highest
gear.
If you are going to drive the vehicle, shift the transmission into the gear
you want. Then shift the transfer case into the range you wan\
t, apply
the regular brakes and release the parking brake.
5 Release the clutch (and the regular brakes) as you normally \
would.
Using a Transfer Case Mounted Power Take-Off (Automatic
Transmission)
When you release the clutch, the power take-off will start.
1 I Set the parking brake.
2. Shift the transfer case into N (Neutral).
3. Shift the transmission into N (Neutral).
4. Engage the power take-off.
If you are going to drive the vehicle, shift the transfer case into the
range you want. Then apply the regular brakes and release the \
parking
brake.
5. Shift the transmission to D (Drive) to start the power take-off.
6. Release the regular brakes to drive the vehicle.
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Engine Fan Noise
This 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 every day
driving conditions the clutch is not engaged. This improves fue\
l economy and
reduces fan noise. Under heavy vehicle loading, trailer towing andlor high
outside temperatures, the fan speed increases when the clutch e\
ngages.
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 Fiat
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, 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 your tire goes flat, the next part shows how to use your jacking equipment
to change a flat tire safely.
Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage by driv\
ing slowly to a
level place. Turn on your hazard warning flashers.
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Service & Appearance Care
.....
Here you will find information about the care of your vehicle . This Section
begins with service and fuel information. and then it shows how to check
important fluid and lubricant levels
. There is also technical information about
your vehicle. and a section devoted to its appearance care
.
Service ........................................................................\
........................................... 6-3
Fuel (Gasoline Engines)
........................................................................\
............... 6-4
Diesel Fuel Requirements and Fuel System
...................................................... 6-6
Checking Things Under the Hood
..................................................................... 6-17
Hood Release
........................................................................\
.......................... 6-18
Cleaning Your Diesel Engine
........................................................................\
.. 6-19
Noise Control System
........................................................................\
............. 6-19
Engine Oil (Except Diesel)
........................................................................\
..... 6.20
Engine Oil (Diesel Engines)
........................................................................\
... 6-26
Air Cleaner
........................................................................\
............................... 6-31
Automatic Transmission Fluid
........................................................................\
. 6-33
Manual Transmission Fluid
........................................................................\
..... 6-36
Hydraulic Clutch
........................................................................\
....................... 6-37
Transfer Case
........................................................................\
.......................... 6-39
Front Axle ........................................................................\
................................. 6-40
Rear Axle
........................................................................\
................................. 6-41
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Cleaning Your Diesel Engine
you spray or pour water or any other liquid on your engine when it is
arm or hot,
or when it is running, you could cause serious damagl o it.
you ever clean the engine, clean it only when it is cold.
Noise Control System
The following information relates to compliance with Federal noi\
se emission
standards for vehicles with a Gross Vehicle Weight Rating (GVW\
R) of more
than 10,000 pounds
(4 536 kilograms). See your maintenance schedule for
information on maintaining the noise control system to minimize degradation
of
the noise emission control system during the life of your vehicle. The noise
control system warranty is given in your Warranty booklet.
These standards apply only to vehicles sold in the United States.
Tampering With Noise Control System Prohibited
Federal law prohibits the following acts or the causing thereof:
1. The removal or rendering inoperative by any person, other t\
han for purposes of maintenance, repair or replacement, of any device
or
element of design incorporated into any new vehicle for the purpose of
noise control, prior to its sale or delivery to the ultimate purchaser or
while it is in use;
or
2. The use of the vehicle after such device or element of design has been
removed or rendered inoperative by any person.
Among those acts presumed to constitute tampering are the acts listed below.
Insulation:
Removal of noise shields or underhood insulation.
Engine:
Removal or rendering engine speed governor, if so equipped, inoperative
so as to allow engine speed to exceed manufacturer specifications.
Fan and Drive:
Removal of fan clutch, if so equipped, or rendering clutch inoperative.
Removal of fan shroud, if so equipped.
Air Intake:
Removal of air cleaner silencer.
Reversing air cleaner cover.
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How to Add Fluid:
Here’s how to add fluid. Refer to the Maintenance Schedule to determine
what kind of fluid to use. See “Recommended Fluids and Lubricants” in the
Index.
1. Remove the filler plug.
2. Add fluid at the filler plug hole. Add only enough fluid to \
bring the fluid
3. Install the filler plug. Be sure that the filler plug is full\
y seated.
level up
to the bottom
of the filler plug hole.
Hydraulic Clutch
112” to
K2376
The hydraulic clutch in your vehicle is self-adjusting. A slight amount of play
(112 inch to an inch) in the pedal is normal.
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Service & Amearance Care
-
When to Check and What to Use;
Refer to the Maintenance Schedule to determine how often you should check
the fluid level in your clutch master cylinder reservoir and what to add. See
“Owner Checks and Services” and “Recommended Fluids and \
Lubricants” in
the Index.
How to Check:
K2344
The proper fluid should be added if the level does not reach the bottom of
the diaphragm when it’s in place in the reservoir. See the instructions on the
reservoir cap.
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Hydraulic Clutch Grease Fitting
A grease fitting is on the clutch housing for lubricating the clutch fork ball
stud. See your Maintenance Schedule for when to lubricate the clutch
housing. See “Recommended Fluids and Lubricants” in the Index for the
proper lubricant to use.
Be sure not to over-fill because you could damage your clutch.
Four- Wheel Drive
Most lubricant checks in this section also apply to four-wheel-drive vehicles.
However, they have two additional systems that need lubrication.
Transfer Case
When to Check Lubricant:
Refer to the Maintenance Schedule to determine how often to check the
lubricant. See “Periodic Maintenance Inspections” in the Index.
How to Check and Add Lubricant:
I
PO230
If the level is below the bottom of the filler plug hole, you’ll need to add
some lubricant. Add enough lubricant to raise the level to the bottom of the
filler plug hole.
What to Use:
Refer to the Maintenance Schedule to determine what kind of lubricant to
use. See “Recommended Fluids and Lubricants” in the Index.
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