1998 GMC SIERRA automatic transmission

Leaving Your Vehicle With the Engine
Running (Automatic Transmission
Only)
I A CATJTION:
It can be dangerous to leave your vehicle with the
engine running. Your vehicle could move
suddenly if the shift lever
is not fully in PARK (P)
with the parking brake firmly set. If you have
four-wheel drive with
a manual transfer case
shift lever and your transfer case is in
NEUTRAL
(N), your vehicle will be free to roll,
even if your shift lever is in PARK
(P). So be sure
the transfer case is in
a drive gear -- not in
NEUTRAL
(N). And, if you leave the vehicle with
the engine running, it could overheat and even
catch fire.
You or others could be injured. Don’t
leave your vehicle with the engine running unless
you have to. If you
have to leave your vehicle with the engine
running, be sure your vehicle
is in PARK (P) and the
parking brake is firmly set before you leave it. After
you
move the shift lever into PARK (P), hold the regular
brake pedal down. Then, see if you can move the shift
lever away from PARK
(P) without first pulling it
toward you. If you can, it means that
the shift lever
wasn’t
fully locked into PARK (P).
Torque Lock (Automatic Transmission)
If you are parking on a hill and you don’t shift your
transmission into PARK (P) properly, the weight of the
vehicle may put
too much force on the parking pawl in
the transmission.
You may find it difficult to pull the
shift lever out of PARK
(P). This is called “torque lock.”
To prevent torque lock, set the parking brake and then
shift
into PARK (P) properly before you leave the
driver’s seat.
To find out how, see “Shifting Into
PARK
(P)” in the Index.
When
you are ready to drive, move the shift lever out of
PARK (P)
before you release the parking brake.
If torque lock does occur, you may need to have another
vehicle push yours a little uphill to take some
of the
pressure from the parking pawl in the transmission,
so
you can pull the shift lever out of PARK (P).
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Shifting Out of PARK (P)
(Automatic Transmission)
Your vehicle has a brake-transmission shift interlock
system. You have to fully apply your regular brakes
before you can shift from PARK
(P) when the ignition is
in
RUN. See “Automatic Transmission” in the Index.
If you cannot shift out of PARK
(P), ease pressure on
the shift lever and push the shift lever all the way up
into PARK
(P) as you maintain brake application. Then,
move the shift lever
to any gear you want.
If you ever hold the brake pedal down but still can’t
shift
out of PARK (P), try this:
1. Turn the key to OFF.
2. Apply and hold the brake until the end of Step 4.
3. Shift to NEUTRAL (N).
4. Start the vehicle and shift to the drive gear you want.
5. Have the brake-transmission shift interlock system
fixed as
soon as you can.
Parking Your Vehicle
(Manual Transmission Models
Only)
Before you get out of your vehicle, put your manual
transmission in REVERSE
(R), turn off the engine, and
firmly apply the parking brake.
If you have four-wheel drive, be sure your transfer case
is in a drive gear. Your vehicle could roll if it isn’t.
If
you are parking on a hill, or if you are pulling a
trailer, see “Towing a Trailer” in
the Index.
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Four-Wheel-Drive Vehicles
(Manual Transfer Case Only)
‘A
-
Shifting the transfer case into NEUTRAL (N) can
cause your vehicle to roll even if the transmission
is in
PARK (P), for an automatic transmission, or
if your vehicle is in gear, for
a manual
transmission.
You or others could be injured.
Make sure the parking brake is firmly set before
you shift the transfer case into NEUTRAL (N).
Use the following procedure to correctly tow your
vehicle on all four wheels:
1.
2.
3.
4.
5.
6.
Firmly set the parking brake.
Place the transmission in
PARK (P) or a manual
transmission in FIRST
(1).
Securely attach the vehicle being towed to the
tow vehicle.
With the engine running, shift the transfer case to
NEUTRAL
(N). See “Four-wheel Drive” in the
Index for the proper procedure to select the neutral
position for your vehicle.
Release the parking brake only after the vehicle
being towed is firmly attached to the towing vehicle.
Turn the ignition to
OFF, The OFF position unlocks the
steering column and reduces battery
drain. Unlocking
the steering column will allow the proper movement
of
the front wheels and tires during towing.
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If You Do Decide To Pull A Trailer
If you do, here are some important points:
0
0
0
0
There are many different laws, including speed limit
restrictions, having to
do with trailering. Make sure
your rig will be legal, not only where you live but
also where you’ll be driving.
A good source for this
information
can be state or provincial police.
Consider using
a sway control if your trailer will
weigh less than
the capacity stamped on your step
bumper. You should always use a sway control
if
your trailer will weigh more than the capacity
stamped
on your step bumper. You can ask a hitch
dealer about sway controls.
Don’t tow a trailer at all during the first
500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
Then, during the first
500 miles (800 km) that you
tow
a trailer, don’t drive over 50 mph (80 kdh) and
don’t make starts at
full throttle. This helps your
engine and other parts
of your vehicle wear in at the
heavier loads.
0 If you have an automatic transmission, you can tow
in OVERDRIVE
(a). You may want to shift the
transmission to
THIRD (3) or, if necessary, a lower
gear selection if the transmission shifts too often
(e.g., under heavy loads and/or
hilly conditions). If
you have
a manual transmission and you are towing
a trailer, it’s better not to use
FIFTH (5) gear. Just
drive
in FOURTH (4) gear (or, as you need to, a
lower gear).
Three important considerations have
to do with weight:
0 the weight of the trailer,
0 the weight of the trailer tongue
0 and the weight on your vehicle’s tires.
Weigl- - 3e Trailer
How heavy can a trailer safely be?
It depends
on how you plan to use your rig. For
example, speed, altitude, road grades, outside
temperature and how much your vehicle is used to
pull a
trailer are all important. And,
it can also depend on any
special equipment that you have
on your vehicle.
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Driving On Grades
Reduce speed and shift to a lower gear before you start
down a long or steep downgrade. If
you don’t shift
down,
you might have to use your brakes so much that
they would
get hot and no longer work well.
On a long uphill grade, shift down and reduce your
speed
to around 45 mph (70 kdh) to reduce the
possibility
of engine and transmission overheating.
If you have an automatic transmission, you can tow in
AUTOMATIC OVERDRIVE
(@). You may want to
shift the transmission
to THIRD (3) or, if necessary, a
lower gear selection
if the transmission shifts too often
(e.g., under heavy loads and/or hilly conditions).
If
you have a manual transmission and you are towing a
trailer, it’s better not to
use FIFTH (5) gear. Just drive in
FOURTH
(4) gear (or, as you need to, a lower gear).
When towing at high altitude
on steep uphill grades,
consider the following: Engine coolant
will boil at a
lower temperature than at normal altitudes. If you turn
your engine off immediately after towing
at high altitude
on steep uphill grades, your vehicle may show signs
similar to engine overheating. To avoid this, let the
engine run while parked (preferably on level ground) with
the automatic transmission in
PARK (P) (or the
manual transmission out of gear and the parking brake
applied) for a few minutes before turning the engine
off.
If you do get the overheat warning, see “Engine
Overheating’’ in
the Index.
Parking on Hills
You really should not park your vehicle, with a trailer
attached, on a
hill. If something goes wrong, your rig
could start to move. People can be injured, and both
your vehicle and the trailer can be damaged.
But
if you ever have to park your rig on a hill, here’s
how to do it:
1.
2.
3.
4.
Apply your regular brakes, but don’t shift into
PARK
(P) yet for an automatic transmission, or into
gear for a manual transmission.
Have someone place chocks under the trailer wheels.
When the wheel chocks are
in place, release the
regular brakes until the chocks absorb the load.
Reapply the regular brakes. Then apply your parking brake and
shift into PARK (P) for an automatic
transmission, or REVERSE (R)
for a manual
transmission.
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5. If you have a four-wheel-drive vehicle,
be sure the transfer case is in
a drive gear and not
in
NEUTRAL (N).
6. Release the regular brakes.
-
/r CAUTIOIA:
It can be dangerous to get out of your vehicle if
the shift lever is not fully in
PARK (P) with the
parking brake firmly set. Your vehicle can roll.
If you have left the engine running, the vehicle
can move suddenly. You or others could be
injured.
To be sure your vehicle won’t move, even
when you’re on fairly level ground, use the steps
that follow.
If you have four-wheel drive and your transfer
case is in
NEUTRAL (N), your vehicle will be free
to
roll, even if your shift lever is in PARK (P). So,
be sure the transfer case is in a drive gear -- not
in
NEUTRAL (N).
When You Are Ready to Leave After
Parking
on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
Start your engine;
Shift into a gear; and
Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly
until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling
a trailer. See the Maintenance Schedule for more
on this. Things that are especially important
in trailer
operation are automatic transmission fluid (don’t
overfill), engine
oil, axle lubricant, belt, cooling system
and brake adjustment. Each of these is covered in this
manual, and the Index will help you find them quickly.
If you’re trailering, it’s a good idea to review these
sections before
you start your trip.
Check periodically
to see that all hitch nuts and bolts
are tight.
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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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