1995 GMC SIERRA automatic transmission

Leaving Your Vehicle With the Engine Running
(Automatic Transmission Models
Only)
A CAUTION:
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 your parking brake is firmly set before you leave
it. After you’ve moved the shift lever into the PARK (P) position, 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 transmission, so
you can pull the shift lever out of PARK (P).
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Engine Exhaust
A CAUTION:
Engine exhaust can kill. It contains the gas carbon monoxide
(CO), which you can’t see or smell. It can cause unconsciousness
and death.
You might have exhaust coming in if:
Your exhaust system sounds strange or different.
Your vehicle gets rusty underneath.
Your vehicle was damaged in a collision.
Your vehicle was damaged when driving over high points on
the road or over road debris.
Repairs weren’t done correctly.
Your vehicle or exhaust system had been modified improperly.
If you ever suspect exhaust is coming into your vehicle:
Drive it only with all the windows down to blow out any CO;
and
Have your vehicle fixed immediately.
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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The from axle portion
of the indicator
diagram will light
up
when you shift into
four-wheel drive.
Some delay between shifting and the indicator's lighting is normal.
If the
indicator light does not light
up, or if the front axle light does not go out
after you shift out of four-wheel drive. have your dealer check your system.
When your headlamps or parking lamps are
on, rotate the thumb wheel next
to the headlamp switch up to brighten, or down to dim, your transfer case
indicator light.
2-WHEEL HIGH (2H)
This setting is for driving
in most street and highway situations. Your
front axle is not engaged
in two-wheel drive.
4-WHEEL HIGH (4H)
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.
0 NEUTRAL (N)
Shift to this setting only when your vehicle needs to be towed or when
using
a power take-off.
0 4-WHEEL LOW (4L)
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 2-WHEEL HIGH (2H)
to &WHEEL HIGH (4H) or from
4-WHEEL HIGH (4H) to 2-WHEEL HIGH (2Hj 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 2-WHEEL HIGH (2H).
To shift
into or out of 4-WHEEL LOW (4L) or NEUTRAL (N):
0 Slow the vehicle to a roll. about 1-3 mph (2-5 km/h) and shift an
automatic transmission into neutral,
or with a manual transmission
press the clutch pedal.
Shift the transfer case shift lever in one continuous motion.
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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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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.
Trailer Lighting Systems Wiring
See “Trailer Wiring Harness” in the Index.
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