1997 GMC SIERRA automatic transmission

Shifting from 2HI to 4HI
Press and release the 4HI switch. This can be done at
any speed, and the front axle will lock automatically
with some delay.
Shifting from 4HI to 2HI
Press and release the 2HI switch. This can be done at
any speed, and
the front axle will unlock automatically
with some delay.
Shifting from 2HI or 4HI to 4LO
To shift from 2HI or 4HI to 4L0, the vehicle must be
stopped or moving less than
3 mph (4.8 km/h) with the
transmission in NEUTRAL
(N). The preferred method
for shifting into 4LO is to have your vehicle moving
1 to
2 mph (1.6 to 3.2 km/h). Press and release the 4LO
switch. You must wait for the 4LO indicator light to stop
flashing and remain illuminated before shifting your
transmission into gear.
Shifting from 4LO to 4HI or 2HI
To shift from 4LO to 4HI or 2H1, your vehicle must be
stopped or moving less than
3 mph (4.8 km/h) with the
transmission
in NEUTRAL (N). The preferred method
for shifting out
of 4LO is to have your vehicle moving
1 to 2 mph (1.6 to 3.2 km/h). Press and release the 4HI
switch. You must wait for the 4HI indicator light to stop
flashing and remain illuminated before shifting your
transmission into gear.
If the 4HI switch is pressed when your vehicle is in
gear and/or moving, the 4HI indicator light will flash for
30 seconds but will not complete the shift unless the
vehicle is moving slower than
3 mph (4.8 km/h) and the
transmission is in NEUTRAL
(N).
If the 4LO switch is pressed when your vehicle is in
gear and/or moving, the 4LO indicator light will flash
for
30 seconds and not complete the shift unless your
vehicle
is moving slower than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL
(N). After 30 seconds the
transfer case will return to 4HI.
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Shifting Into PARK (P) (Automatic
Transmission
Models Only)
It can be danL *ous 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). If
you’re pulling a trailer, see “Towing
a Trailer”
in the Index.
2. Move the shift lever into PARK (P) position like this:
Pull the lever toward you.
1. Hold the brake pedal down with your right foot and
set the parking brake.
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0 Move the lever up as far as it will go.
3. If you have four-wheel drive, be sure the transfer
case is in a drive gear
-- not in NEUTRAL (N).
4. Turn the ignition key to LOCK.
5. Remove the key and take it with you. If you can
leave your vehicle with the ignition key in your
hand, your vehicle
is in PARK (P).
Leaving Your Vehicle With the Engine
Running (Automatic Transmission
Models Only)
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.
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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).
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.
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Engine Exhaust
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:
0 Your exhaust system sounds strange
0 Your vehicle gets rusty underneath.
Your vehicle was damaged in a collision.
0 Your vehicle was damaged when driving over
high points on the road or over road debris.
0 Repairs weren’t done correctly.
0 Your vehicle or exhaust system had been
If you ever suspect exhaust is coming into
your vehicle:
Drive it only with all the windows down to
0 Have your vehicle fixed immediately,
or
different.
modified improperly.
blow out any
CO; and
Running Your Engine While You’re
Parked (Automatic Transmission)
It’s better not to park with the engine running. But if
ever have
to, here are some things to know.
I
Idling the engine with the air system control
off could allow dangerous exhaust into
your vehicle (see the earlier Caution under
‘(Engine Exhaust”).
Also, idling in a closed-in place can let deadly
carbon monoxide
(CO) into your vehicle even if
the fan switch is at the highest setting. One place
this can happen
is a garage. Exhaust -- with
CO -- can come in easily. NEVER park in a
garage with the engine running.
Another closed-in place can be a blizzard. (See
“Blizzard” in the Index.)
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a If you have an automatic transmission, you can tow
in 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).
Three important considerations have to do with weight:
the weight of the trailer,
the weight of the trailer tongue
and the weight on your vehicle’s tires.
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. Use
one of the following charts to determine how much
your vehicle can weigh, based upon your vehicle model
and options.
Maximum trailer weight is calculated assuming the
driver and one passenger are in the tow vehicle and it
has all
the required trailering equipment. The weight of
additional optional equipment, passengers and cargo in
the tow vehicle must be subtracted from the maximum
trailer weight.
Above the
2,000 lbs. (908 kg) trailer rating, the engine
oil cooler is required
on C/K-1500 and C/K-2500
models with gas engines. Refer to the Trailering Guide
for oil cooler recommendations.
Above the
5,000 lbs. (2 270 kg) trailer rating, heavy-duty
or gas shock absorbers are required on
C- 1500 models,
and heavy-duty shock absorbers or the off-road chassis
package are required on
K- 1500 models.
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Turn Signals When Towing a Trailer
The 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 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 km/h) to reduce the
possibility of engine and transmission overheating. If you have an automatic transmission, you can tow
in
AUTOMATIC 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).
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.
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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. Apply your regular brakes, but don't shift into
PARK
(P) yet for an automatic transmission, or into
gear for a manual transmission.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb
the load.
4. 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.
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.
c
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).
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