1994 GMC SIERRA transmission

What can you do about highway hypnosis? First, be aware that it can
happen.
Then here are some tips:
0 Make sure your vehicle is well ventilated, with a comfortably cool
interior.
Keep your eyes moving. Scan the road ahead and to the sides. Check
your mirrors and your instruments frequently.
0 If you get sleepy, pull off the road into a rest, service, or parking area
and take a nap, get some exercise, or both.
For safety, treat drowsiness
on the highway
as an emergency.
Hill and Mountain Roads
Driving on steep hills or mountains is different from driving in flat or
rolling terrain.
If you drive regularly in steep country, or if you're planning to visit there,
here are some tips that can make your trips safer and more enjoyable. (See
"Off-Road Driving" in the Index for information about driving off-road.)
0 Keep your vehicle in good shape. Check all fluid levels and also the
brakes, tires, cooling system and transmission. These parts can work
hard
on mountain roads.
0 Know how to go down hills. The most important thing to know is this:
let your engine do some of the slowing down. Shift to a lower gear
when you go down
a steep or long hill.
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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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Power Take-Off (PTO)
NOTICE:
If you will be using the PTO while the vehicle remains in one
place, drive the vehicle to warm it up before operating the
PTO.
Don’t use the PTO for more than four hours without driving
your vehicle again. If you don’t follow these guidelines, your
transfer case or transmission could be damaged.
NOTICE:
Don’t have a PTO that will exceed 35 horsepower installed on
your vehicle. It could damage your transmission or transfer
case.
Before using a power take-off, refer to the manufacturer’s or installer’s
instructions.
To engage a power take-oft
1. Set the 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 into the gear
you want.
Then shift the transfer case into the range you want (if you
have four-wheel drive), apply the regular brakes and release the
parking brake.
4. Release the clutch (and the regular brakes) as you normally would.
When
you release the clutch, the power take-off will start.
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, shift the transmission into the highest gear.
4. Engage the power take-off.
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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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When you call, tell the towing service:
That your vehicle has rear-wheel drive, or that it has the four-wheel
drive option.
The make, model, and year of your vehicle.
Whether you can move the shift lever for the transmission and transfer
case,
if you have one.
If there was an accident, what was damaged.
1
When your vehicle is being towed, have the ignition key off. The steering
wheel should be clamped
in a straight-ahead position, with a clamping
device designed for towing service.
Do not use the vehicle’s steering
column lock for this. The transmission and transfer case,
if you have one,
should be in Neutral and
the parking brake released.
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