1995 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
Keep your eyes moving. Scan the road ahead and to the sides. Check
interior.
your mirrors and your instruments frequently.
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
I
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.)
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.
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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1 A CAUTION:
If you don’t shift down, your brakes could get so hot that they
wouldn’t work well. You would then have poor braking or even
none going down a hill.
You could crash. Shift down to let your
engine assist your brakes on a steep downhill slope.
A CAUTION:
Coasting downhill in NEUTRAL (N) or with the ignition off is
dangerous. Your brakes will have to
do all the work of slowing
down. They could get
so hot that they wouldn’t work well. You
could crash. Always have your engine running and your vehicle
in gear when you
go downhill.
Know how to go uphill. You may want to shift down to a lower gear.
The lower gears help cool your engine and transmission, and you can
climb
the hill better.
Stay in your own lane when driving on two-lane roads in hills or .
mountains. Don’t swing wide or cut across the center of the road. Drive
at speeds
that let you stay in your own lane.
As you go over the top of a hill, be alert. There could be something in
your lane, like a stalled car or an accident.
You may see highway signs on mountains that warn of special
problems. Examples are long grades, passing or no-passing
zones, a
falling rocks area, or winding roads. Be alert
to these and take
appropriate action.
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c
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.
NOTICE:
Using a power winch with the transmission in gear may damage
the transmission. When operating a power winch, always leave
the transmission in NEUTRAL
(N).
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 have a PTO that will exceed 35 horsepower installed on
your vehicle, it could damage the transfer case or transmission.
When having
a PTO installed on your vehicle, make sure that it
will not exceed 35 horsepower.
Before using a power take-off, refer to the manufacturer’s or installer’s
instructions.
NOTICE:
Using a PTO while operating in one place before the vehicle has
reached normal operating temperature can damage the transfer
case or transmission.
If you will be using the PTO while
operating in one place, drive and warm up the vehicle before
using the PTO.
To engage a power take-off
1. Set the parking brake.
2. Shift the transmission into NEUTRAL (N).
3. Hold the clutch pedal down and engage the power take-off.
I NOTICE:
Using a PTO for more than four hours without driving your
vehicle can damage the transfer case or transmission.
If using a
PTO for more than four hours without dr$ving your vehicle,
drive your vehicle for
a while to allow the transfer case and
transmission to cool.
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.
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Using a Transfer Case Mounted Power Take-Off
(Manual Transmission)
1. Set the parking brake.
2. Shift the transfer case into NEUTRAL (N).
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.
If you are going to drive the vehicle, shift the trans~nission into the gear
you want, Then shift the transfer case into the range you want, apply
the regular brakes and release the parking brake.
5. 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
(Automatic Transmission)
1.
2.
3.
4.
5.
6.
Set the parking brake.
Shift the transfer case into NEUTRAL
(N).
Shift the transmission into NEUTRAL (N).
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.
Shift the transmission to DRIVE
(3) to start the power take-off.
Release
the regular brakes to drive the vehicle.
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Most vehicles are ready for some trailer towing. If yours was built with
trailering options,
as many are, it’s ready for heavier trailers. But trailering
is different than just driving your vehicle by itself. Trailering means changes
in handling, durability, and fuel economy. Successful, safe trailering takes
correct equipment, and
it has to be used properly.
That’s the reason for this part.
In it are many time-tested, important
trailering tips and safety rules. Many of these are important for your safety
and that of your passengers.
So please read this section carefully before you
pull a trailer.
If You Do Decide To Pull A Trailer
If you do, here are some important points.
e
e
a
0
a
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 4,000 pounds
(I 800 kg) or less. You should always use a sway control if your trailer
will weigh more than
4,000 pounds (1 800 kg). 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.
If you have an automatic transmission, you should use DRIVE (3) (or,
as you need to, a lower gear) when towing a trailer. Operating your
vehicle in DRIVE
(3) when towing a trailer will minimize heat
build-up 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
(5) gear. Just drive in FOURTH (4) gear (or, as you need to, a lower
gear).
Three important considerations have
to do with weight:
Weight of the 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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Making Turns
I NOTICE:
Making very sharp turns while trailering could cause the traile\
r to come in contact with the vehicle. Your vehicle could be
damaged. Avoid making very sharp turns while trailering.
When you’re turning with a trailer, make wider turns than normal. Do this
so your trailer won’t strike soft shoulders, curbs, road signs, trees, or other
objects. Avoid jerky or sudden maneuvers. Signal well in advance.
Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle has to have extra wiring (included in
the optional trailering package). The green arrows
on your instrument panel
will flash whenever
you signal a turn or lane change. Properly hooked up,
the trailer lamps will also flash, telling other drivers you’re about to turn,
change lanes or stop.
When towing a trailer, the green arrows on your instrument panel will flash
for
turns even if the bulbs on the trailer are burned out. Thus, you may think
drivers behind
you are seeing your signal when they are not. It’s important
to check occasionally to be sure the trailer bulbs are still working.
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 kmh) to reduce the possibility of engine and transmission overheating.
If you have an automatic transmission
you should use DRIVE (3) (or, as
you need to, a lower gear) when towing a trailer. Operating your vehicle in
DRIVE (3) when towing a trailer will minimize heat build-up 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 (5) gear. Just drive in FOURTH (4) gear (or, as you need
to, a lower gear).
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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 (Pj (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.
5.
6.
Apply your regular brakes, but don’t shift into PARK (P) 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 PARK (P), or REVERSE (Rj for a manual transmission.
If you have
a four-wheel-drive vehicle, be sure the transfer case is in a
drive gear-not in NEUTRAL
(N).
Release the regular brakes.
A CAUTION:
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 rofl.
If you have Ieft 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).
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