1998 GMC SIERRA transmission

Using a Transfer Case Mounted Power
Take-Off (Automatic Transmission)
1.
2.
3.
4.
5.
6.
7.
Set the parking brake.
Turn the ignition off.
Shift the transfer case into NEUTRAL
(N).
Shift the transmission into NEUTRAL (N).
Engage the PTO.
If you are going to drive the vehicle. shift the
transfer case into the range you want. Turn
the
ignition to START. Then apply the regular brakes
and release the. parking brake.
Shift the transmission to THIRD
(3) to start the PTO.
Release the regular brakes to drive the vehicle.
Disengaging a Power Take-OFF
1. Turn the ignition off.
2. Put the transmission in PARK (P).
3. Release the PTO
4. Restart the engine.
Step-Bumper Pad
If your vehicle has a rear step bumper, it may be
equipped with
a rear step pad at the center of
the bumper.
If you will be using the
bumper to tow a trailer,
you
must remove the center
cutout circle to install the
trailer ball.
You must also
remove both outer cutouts
to attach the trailer safety chains.
To remove the pad,
lift the
edge of the pad from the
rear of the bumper and
swing it forward. When the
pad releases from the
bumper holes,
lift the
pad off.
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2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren’t touching
each other. If they are, it could cause a ground
connection
you don’t want. You wouldn’t be able
to start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility
of the vehicles rolling, set
the parking brake firmly on both vehicles involved
in the jump start procedure. Put an automatic
transmission in
PARK (P) or a manual transmission
in NEUTRAL (N).
If you have a four-wheel-drive
vehicle, be sure the transfer case is not in
NEUTRAL
(N).
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlets. Turn
off all lamps
that aren’t needed as well as radios. This will avoid
sparks and help save both batteries. In addition, it
could save your radio!
I NOTICE:
If you leave your radio on, it could be badly
damaged. The repairs wouldn’t be covered by
your warranty.
4. Open the hoods and locate the batteries. Find the
positive
(+) and negative (-) terminals on each battery.
If your vehicle has air conditioning, the auxiliary
electric fan under the hood can start up even
when the engine is not running and can injure
you. Keep hands, clothing and tools
away from
any underhood electric fan.
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11. Try to start the vehicle with the dead battery.
If it won’t start after
a few tries, it probably
needs service.
12. Remove the cables in reverse order to prevent
electrical shorting. Take care that they don’t touch
each other or any other metal.
A. Heavy Metal Engine Part
B. Good Battery
C. Dead Battery
Towing Your Vehicle
Try to have your GM dealer or a professional towing
service tow your vehicle. See “Roadside Assistance’’
in
the Index.
If your vehicle has been changed since it was
factory-new, by adding such things
as fog lamps, aero
skirting, or special tires and wheels, these instructions
may not be correct.
Before you do anything, turn on the hazard
warning flashers.
When you call, tell the towing service:
0 That your vehicle has rear-wheel-drive, or that it has
the four-wheel-drive option.
0 The make, model and year of your vehicle.
Whether you can move the shift lever for the
0 If there was an accident, what was damaged.
When
the towing service arrives, let the tow operator
know that this manual contains detailed towing
instructions and illustrations. The operator may want to
see
them.
transmission and transfer case, if you have one.
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A CAUTION:
To help avoid injury to you or others:
0
0
0
0
0
a
0
Never let passengers ride in a vehicle that is
being towed. Never tow faster than safe or posted speeds.
Never tow with damaged parts not
fully secured.
Never get under your vehicle after it has
been lifted by the tow truck.
Always use separate safety chains on each
side when towing a vehicle.
For pickups (except cab chassis models),
use T-hooks on front of vehicle, J-hooks
on rear.
For cab chassis models, use J-hooks on
front and rear of vehicle.
A CAUTION:
A vehicle can fall from a car carrier if it isn’t
adequately secured. This can cause a collision,
serious personal injury and vehicle damage. The
vehicle should be tightly secured with chains or
steel cables before it is transported.
Don’t use substitutes (ropes, leather straps,
canvas webbing, etc.) that can be cut by sharp
edges underneath the towed vehicle.
Don‘t have your vehicle towed on the drive wheels
unless you must.
If the vehicle must be towed on the
drive wheels. be sure to follow the speed and distance
restrictions later
in this section or your transmission will
be damaged. If these limitations must be exceeded, then
the drive wheels have
to be supported on a dolly.
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Front Towing
Two- Wheel-Drive Vehicles
Tow Lirnits -- 35 nzph (55 kdh), 50 miles (80 kr.n/h)
If your vehicle is two-wheel drive, use the
following directions:
I. Engage the parking brake.
2. Turn the ignition key to OFF.
3. Clamp the steering wheel in a straight-ahead position
with a clamping device designed for towing service.
(Do not use the vehicle’s steering column lock for this.)
4. Put an automatic or a manual transmission in
NEUTRAL (N).
5. When the vehicle is hooked up, release the
parking brake.
Four-Wheel-Drive Vehicles (Manual Transfer Case)
Tow Lirnits -- 55 rnph (88 knzdh) or legtrl speed limit,
distance
is unlimited
If your vehicle is four-wheel drive with a manual
transfer case, use the following directions:
1. Engage the parking brake.
2. Turn the ignition key to OFF.
3. Clamp the steering wheel in a straight-ahead position
with
a clamping device designed for towing service.
(Do not use the vehicle’s steering column lock for this.)
4. Put an automatic transmission in PARK (P), or a
manual transmission
in FIRST (1).
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5. Put the transfer case in NEUTRAL (N). See
“Four-wheel Drive” in the Index
for the proper
procedure to select NEUTRAL
(N).
6. When the vehicle is hooked up, release the
parking brake.
4. Put the transmission in NEUTRAL (N).
5. Put the transfer case in 2 High (2HI).
6. When the vehicle is hooked up, release the
parking brake.
Four- Wheel Drive-Vehicles (Electronic
Transfer Case)
Tow Limits -- 35 mph (55 krdh), 50 miles (80 krn/l1)
If your vehicle is four-wheel drive with an electronic
transfer case, use the following directions:
1. Engage the parking brake.
2. Turn the ignition key to OFF.
3. Clamp the steering wheel in a straight-ahead position
with a clamping device designed for towing service.
(Do not use the vehicle’s steering column lock for this.)
NOTICE:
If your vehicle is equipped with an electronic
transfer case and the tow limits must be
exceeded, a towing dolly must be used under the rear wheels or vehicle/powertrain damage
will occur.
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Rear Towing
Two-Wheel-Drive Vehicles
Tow Limits -- 55 ~zph (88 krdh) or legal speed limit,
distmce is ditnited
If your vehicle is two-wheel drive, use the
following directions:
1. Turn the ignition key to OFF.
2.
3.
4.
5.
Engage the parking brake.
Clamp the steering wheel in a straight-ahedd position
with a clamping device designed for towing service.
(Do not use the vehicle’s steering column lock for this.)
Put an automatic transmission
in PARK (P), or a
manual transmission in FIRST (1).
When the vehicle is hooked up, release the
parking brake.
Four-Wheel-Drive Vehicles (Manual Transfer Case)
If your vehicle is four-wheel drive with a manual
transfer case, use the following directions:
1.
2.
3.
4.
Engage the parking brake.
Turn the ignition
key to ON.
Clamp the steering wheel in a straight-ahead position
with a clamping device designed for towing service.
(Do not use the vehicle’s steering column lock for this.)
Put an automatic transmission
in PARK (P), or a
manual transmission in FIRST (1).
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5. Put the transfer case in NEUTRAL (N). See
“Four-Wheel Drive’’
in the Index for the proper
procedure to select NEUTRAL
(N).
6. When the vehicle is hooked up. release the
parking brake.
7. Turn the ignition key to OFF.
Four- Wheel-Drive Vehicles (Electronic
Transfer Case)
Eml Limits -- 35 mph (55 km/JZ), 50 milc?s (80 kndh)
If your vehicle is four-wheel drive with an electronic
transfer case, use the following directions:
I. Engage the parking brake.
2. Turn the ignition key to ON.
3. Clamp the steering wheel in a straight-ahead position
with
a clamping device designed for towing service.
(Do not use the vehicle’s steering column lock for this.)
4. Put the transmission in NEUTRAL (N).
5. Put the transfer case in 2 High (2HI).
6. When the vehicle is hooked up, release the
parking brake.
7. Turn the ignition key to OFF.
NOTICE:
If your vehicle is equipped with four-wheel drive
and the towing limits must be exceeded, a towing
dolly must be used under the front wheels or
vehicle/powertrain damage will occur.
I NOTICE:
Towing pickup models from the rear while loaded
with heavy cargo may cause the frame side rails
to flex sufficiently to allow the pickup box to
contact the cab and could cause damage to the
cab and/or box.
Engine Overheating (Gasoline Engine)
You will find a coolant temperature gage on your
vehicle’s instrument panel. See “Engine Coolant
Temperature Gage”
in the Index.
If your vehicle has a diesel engine, see “Engine
Overheating”
in the Diesel Engine Supplement.
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