1994 GMC SIERRA automatic transmission

5. Remove the key and take it with you. If you can walk away from your
vehicle with
the ignition key in your hand, your vehicle is in “P”
(Park).
Leaving Your Vehic/e With the Engine Running
(Automatic Transmission Models Only)
If you have to leave your vehicle with the engine running, be sure your
vehicle is
in “P” (Park) and your parking brake is firmly set before you
leave it. If you have four-wheel drive with a manual transfer case shift
lever, be sure that the transfer case
is in a drive gear - not in “N” (Neutral).
After you’ve moved the
shift lever into the “P’ (Park) position, hold the
regular brake pedal down. Then, see if
you can move the shift lever away
from “P” (Park) without first pulling it toward
you. If you can, it means that
the shift lever wasn’t
fully locked into “P” (Park).
Torque Lock (Automatic Transmission)
If you are parking on a hill and you don’t shift your transmission into “P”
(Park) 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
“P’ (Park). This is called “torque lock.” To prevent torque lock,
set the parking brake and then shift into “P’ (Park) properly before you
leave
the driver’s seat. To find out how, see “Shifting Into ‘P’ (Park)” in the
Index.
When you are ready to drive, move the
shift lever out of “P” (Park)
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 transmission, so
you can pull the shift lever out of “P’ (Park).
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Engine Exhaust Running Your Engine While You’re Parked
(Automatic Transmission)
It’s better not to park with the engine running. But if you ever have to, here
are some things
to know.
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When your headlights or parking lights are on, rotate the dial to the right of
your headlight switch up
to brighten, or down to dim, your transfer case
indicator light.
2H (2-Wheel High): This setting is for driving in most street and highway
situations. Your front axle is not engaged
in two-wheel drive.
4H (4-Wheel High): This setting engages your front axle to help drive your
vehicle. Use
4H when you need extra traction, such as on wet or icy roads,
or in most off-road situations.
N (Neutral): Shift to this setting only when your vehicle needs to be towed
or when using a power take-off.
4L (4-Wheel Low): This setting also engages your front axle to give you
extra power, but should be used only for off-road driving.
You can shift from
2H to 4H or from 4H to 2H while the vehicle is moving.
Your front axle will engage faster if you take your foot off of the accelerator
for a few seconds after you shift.
In extremely cold weather it may be
necessary to stop or slow the vehicle to shift
out of 2H.
To shift into or out of 4L or “N” (Neutral):
Slow the vehicle to a roll, about 1-3 mph (2-5 kdh) and shift your
transmission into neutral.
0 Shift the transfer case shift lever in one continuous motion.
Don’t pause
in “N” (Neutral) as you shift the transfer case into 4L, or your
gears could clash.
Remember that driving
in 4H or 4L may reduce fuel economy. Also, driving
in four-wheel drive on dry pavement could cause your tires to wear fdster
and make your transfer case harder to shift.
Front Axle Locking Feature
The front axle locks and unlocks automatically when you shift the transfer
case. Some delay
for the axle to lock or unlock is normal. If the outside
temperature is very hot, or the vehicle has been used under hard driving
conditions, there may be
a slight delay for the axle to unlock.
Whenever you are
in four wheel drive, the rear wheel anti-lock brake
system does not operate. The regular brake system operates normally. When
you shift back into two-wheel drive, the anti-lock brake system will
operate.
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I
Run your engine only as long as you must. This saves fuel. When you run
the engine, make it go a little faster than just idle. That is, push the
accelerator slightly. This uses less fuel for the heat that you get and it keeps
the battery (or batteries) charged.
You will need a well-charged battery (or
batteries) to restart the vehicle, and possibly for signaling later on with your
headlights. Let the heater run for awhile.
If you have a diesel engine, you may have to run it at a higher speed to get
enough heat. Then, shut the engine off and close
the window almost all the
way to preserve the heat. Start the engine again and repeat this only when
you feel really uncomfortable from the cold. But do it as little as possible.
Preserve the fuel
as long as you can. To help keep warm, you can get out of
the vehicle and do some fairly vigorous exercises every half hour or so until
help comes.
Power Winches
If you wish to use a power winch on your vehicle, only use it when your
vehicle
is stationary or anchored.
When operating a power winch on your vehicle, always leave the\

transmission
in "N" (Neutral). Leaving a automatic transmission
in "P" (Park) while using a power winch may damage the
transmission.
Also, leaving an automatic or manual transmission
in gear while using a power winch may damage the
transmission.
Use the regular brakes, set the parking brake, or block the wheels to keep
your vehicle
from rolling.
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If you are going to drive the vehicle, shift the transmission into th\
e gear
you want. Then shift the transfer case into the range you want, apply
the regular brakes and release the parking brake.
When you release the clutch, the power take-off will start.
5. Release the clutch (and the regular brakes) as you normally \
would.
Using a Transfer Case Mounted Power Take-Off
(Automatic Transmission)
1. 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 powe\
r take-off.
6. Release the regular brakes to drive the vehicle.
Towing a Trailer
NOTICE:
Pulling a trailer improperly can damage your vehicle and result\

in costly repairs not covered by your warranty.
To pull a trailer
correctly, follow the advice in this section, and see your Veh\
icle
dealer for important information about towing a trailer with
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 km/h) to reduce the possibility of engine and transmission overheating.
When towing at high altitude with steep uphill grades,you need to consider
the following information. The lower atmospheric pressure at high altitude
allows your vehicles engine coolant to boil at a lower temperature than at
normal altitudes.
If you immediately turn your engine off after towing at high altitude with
steep uphill grades, your vehicle may show signs similar
to engine
overheating.
To avoid this, let your vehicle operate in a parked position with
the transmission in
“N” (Neutral) for a few minutes before you turn off the
engine. If you do get the overheat warning, see “Engine Overheating” in
the Index.
If you have an automatic transmission, you should use
“D” (or, as you need
to, a lower gear) when towing a trailer. Operating your vehicle in
“D” when
towing a trailer will minimize heat buildup and extend the life
of your
transmission.
If you have a manual transmission and
you are towing a trailer, it’s better
not to use fifth gear. Just drive in fourth gear (or, as you need to, a lower
gear).
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.
5.
6.
Apply your regular brakes, but don’t shift into “P’ (Park) yet, or in 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.
Re-apply the regular brakes. Then apply your parking brake, and then
shift to
“P7, (Park), or “R” (Reverse) for a manual transmission.
If
you have a four-wheel-drive vehicle, be sure the transfer case is in a
drive gear-not in
“N7 (Neutral).
Release
the regular brakes.
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Other Warning Devices
If you carry reflective triangles, you can use them to warn others. Set one up
at the side of the road about 300 feet (1 00 m) behind your vehicle.
Jump Starting
If your battery (or batteries) has run down, you may want to use another-
vehicle
and some jumper cables to start your vehicle. But please follow the
steps below to do it safely.
things
NOTICE:
Ignoring these steps could result in costly damage to your
vehicle that wouldn’t be covered by your vehicle warranty.
Trying
to start your vehicle by pushing or pulling it could
damage your vehicle, even if you have a manual transmission.
And if you have an automatic transmission, it won’t start that
way.
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To Jump Start Your Vehicle
1. Check the other vehicle. It must have a 12-volt battery with a negative
ground system.
I NOTICE:
If the other system isn’t a 12-volt system with a negative
ground, both vehicles can be damaged.
If you have a diesel engine vehicle with two batteries (or more), you
should know before
you begin that, especially in cold weather, you may
not be able to get enough power from
a single battery in another
vehicle to start your diesel engine.
If your vehicle
has more than one battery, use the battery that’s on the
passenger side
of the vehicle - this will reduce electrical resistance.
sure the vehicle’s 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.
You could be injured
if the vehicles roll. Set the parking brake firmly
on each vehicle. Put an automatic transmission
in “P” (Park) or a
manual transmission in “N” (Neutral). If you have a four-wheel-drive
vehicle, be sure
the transfer case is not in “N” (Neutral).
2. Get the vehicles
close enough
so the jumper cables can reach, but be
3. Turn off the ignition on both vehicles. Turn off all lights that aren’t
needed, and radios. This will avoid sparks and help save both batteries.
And it could save
your radio!
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.
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