1998 GMC SIERRA transmission

If you get the overheat warning with no sign of steam,
try this for
a minute or so:
1. If you have an air conditioner, turn it off.
2. Turn on your heater to full hot at the highest fan
speed and open the window
as necessary.
3. If you’re in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving
-- AUTOMATIC OVERDRIVE (@)
for automatic transmissions.
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about
10 minutes.
If the warning doesn’t come back on, you can
drive normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there’s still no sign
of steam, push the accelerator until
the engine speed
is about twice as fdst as normal idle
speed. Bring the engine speed back to normal idle speed
after two or three minutes. Now see if the warning stops.
But then, if you still have the warning, turn ofthe
engine
and get everyone out of the vehicle until it
cools down.
You may decide not to lift the hood but to get service
help right away.
Cooling System -- Gasoline Engines
When you decide it’s safe to lift the hood, here’s what
you’ll see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Fan(s)
5-15
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Engine Fan Noise If a Tire Goes Flat
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
partially disengages. 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 hils, 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.
5-23
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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.
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. nrn 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.
V
The following steps will tell you how to use the jack and
change a tire.
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J
E
I
F
C
Chassis Cab Models
A. Nut
B. Retainer
C. Jack Handle Extension
D. Jack Handle Extension
E. Wheel Wrench
E Jack and Tool
Storage Box
G. Ratchet
H. Jack Handle
I. Tool Retainer
J. Jack
If You’re Stuck: In Sand, Mud,
Ice or Snow
What you don’t want to do when your vehicle is stuck is
to spin your wheels too fast. The method known as
“rocking” can help
you get out when you’re stuck, but
you must use caution.
A CAUTION:
If you let your tires spin at high speed, they can
explode, and you or others could be injured. And,
the transmission or other parts
of the vehicle can
overheat. That could cause an engine
compartment fire or other damage. When you’re
stuck, spin the wheels as little as possible. Don’t
spin the wheels above
35 mph (55 km/h) as shown
on the speedometer.
5-36
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NOTICE:
Spinning your wheels can destroy parts of your
vehicle as well as the tires. If you spin the wheels
too fast while shifting your transmission back
and forth,
you can destroy your transmission. I
For information about using tire chains on your vehicle,
see “Tire Chains”
in the Index.
Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will
clear the area around your front wheels. If
you have a
four-wheel drive vehicle, shift into
4HI. Then shift back
and forth between
REVERSE (R) and a forward gear
(or with a manual transmission, between FIRST
(1) or
SECOND (2) and REVERSE (R)), spinning the wheels
as little as possible. Release the accelerator pedal while
you shift, and press lightly on the accelerator pedal
when the transmission is
in gear. If that doesn’t get
you out after a few tries, you may need to be towed out.
Or,
you can use your recovery hooks if your vehicle has
them.
If you do need to be towed out, see “Towing
Your Vehicle”
in the Index.
Using the Recovery Hooks
Your vehicle may be equipped with recovery hooks.
The recovery hooks are provided
at the front of your
vehicle.
You may need to use them if you’re stuck
off-road and need to be pulled to some place where
you can continue driving.
5-37
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Section 6 Service and 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 part devoted to its appearance care.
6-2
6-3
6-5
6-6
6- 8
6-9
6- 13
6- 14
6-18
6-2
I
6-24
6- 25
6-26
6-26
6-28 6-32
6-32 Service
Fuel (Gasoline Engine)
Fuels
in Foreign Countries (Gasoline Engines)
Filling Your Tank (Gasoline Engine)
Filling a Portable Fuel Container
Checking Things Under the Hood
Noise Control System
Engine Oil (Gasoline Engine)
Air Cleaner Filter (Gasoline Engine)
Automatic Transmission Fluid
Manual Transmission Fluid
Hydraulic Clutch
Rear Axle
Four-wheel Drive
Engine Coolant Radiator Pressure Cap (Gasoline Engine)
Thermostat
, 6-33
6-3 3
6-35
6-39
6-39
6-50
6-5
1
6-6 1
6-62
6-65 6-69
6-70
6-70
' 6-76
6-77 6-79 Power
Steering Fluid
Windshield Washer Fluid
Brakes
Battery
Bulb Replacement
Windshield Wiper Blade Replacement
Tires
Appearance Care
Cleaning the Inside
of Your Vehicle
Cleaning the Outside of Your Vehicle
Appearance Care Materials Chart
Vehicle Identification Number (VIN)
Electrical System Replacement
Bulbs
Capacities and Specifications
Air Conditioning Refrigerants
6-1
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“VORTEC” 4300,5000,5700 Engine, “VORTEC” 5700 engine shown, locations for other engines similar.
When you lift
up the hood you’ll see:
A. Battery
G. Automatic Transmission L. Clutch Fluid Reservoir
B. Air Cleaner
Dipstick
(If Equipped) (If Equipped)
C. Radiator Cap H. Fan M. Windshield Washer Fluid
D. Coolant Recovery Tank I. Power Steering Fluid Reservoir Reservoir
E. Air Filter Restriction Indicator J. Engine Oil Fill N. FuseRelay Center
F. Engine Oil Dipstick K. Brake Fluid Reservoir
6-11
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“VORTEC” 7400 Engine
A. Battery
B. Coolant Recovery Tank
C. Air Cleaner
D. Radiator Cap
E. Air Filter Restriction Indicator
F. Engine Oil Dipstick
G. Automatic Transmission L. Clutch Fluid Reservoir
Dipstick (If Equipped)
(If Equipped)
H. Engine Oil Fill M. Windshield Washer
I. Fan Fluid Reservoir
J. Power Steering Fluid Reservoir N. Fusemelay Center
K. Brake Fluid Reservoir
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