1998 GMC ENVOY Owners Manual

FIRST (1): This position gives you even more power
but lower fuel economy than SECOND (2). You can use
it on very steep hills, or in deep snow or mud. If the
selector lever
is put in FIRST (1) while the vehicle is
moving forward, the transmission won’t shift into
FIRST (1) until the vehicle is going slowly enough.
NOTICE:
If your rear wheels can’t rotate, don’t try to
drive. This might happen if you were stuck in
very deep sand or mud or were up against a solid
object. You could damage your transmission.
Also, if you
stop when going uphill, don’t hold
your vehicle there with only the accelerator
pedal. This could overheat and damage the
transmission.
Use your brakes or shift into
PARK
(P) to hold your vehicle in position
on a hill.
Parking Brake
To set the parking brake. hold the regular brake pedal
down with your
right foot. Push down the parking brake
pedal with your left foot.
If the ignition is on, the brake
system warning light
will come on.
To release the parking brake, hold the regular brake
pedal down.
Pull the BRAKE RELEASE lever. It is located on the
bottom of the driver’s side of the instrument panel.
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NOTICE:
Driving with the parking brake on can cause
your rear brakes to overheat.
You may have to
replace them, and you could also damage other
parts of your vehicle.
If you are towing a trailer and you must park on a hill,
see “Towing
a Trailer” in the Index. That section shows
what to do first to keep the trailer from moving.
Shifting Into PARK (P)
L
I
L!h CAUTL .:
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. Always put the shift lever fully in
PARK
(P) with the parking brake firmly set. If
you’re pulling a trailer, see “Towing a Trailer” in
the Index.
1. Hold the brake pedal down with your right foot and
set the parking brake.
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2. Move the shift lever into PARK (P) position
like this:
Hold in the button on the lever.
Push the lever all the way toward the front of
the vehicle.
3. Turn the ignition key to LOCK,
4. Remove the key and take it with you. If you can
leave your vehicle with the key, your vehicle
is in
PARK
(P).
Leaving Your Vehicle With the
Engine Running
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. 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 PARK
(P), hold the
regular brake pedal down. Then, see if you can move the
shift lever away from PARK
(P) without pressing the
button
on the shift lever. If you can, it means that the
shift lever wasn’t fully locked into PARK
(P).
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Torque Lock Shifting Out of Park (P)
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). Your
vehicle has
a Brake-Transmission Shift Interlock
(BTSI). You have to fully apply your regular brake
before you
can shift from PARK (P) when the ignition is
in RUN. See “Automatic Transmission Operation”
in
the Index.
If you cannot shift out of PARK (P), ease pressure on
the shift lever
-- push the shift lever all the way into
PARK
(P) as you maintain brake application. Then
move
the shift lever into the gear you want. You must
press the shift lever button on the console shift lever.
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 then shift to the drive gear
you want.
5. Have the vehicle fixed as soon as you can.
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P -ing Over nqs That Burn Engine Exhaust
Things that can burn could touch hot exhaust
parts under your vehicle and ignite. Don't park
over papers, leaves, dry grass or other things that
can burn. 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
Your vehicle gets rusty underneath.
0 Your vehicle was damaged in a collision.
Your vehicle was damaged when driving
over high points on the road or over
road debris. or different.
0 Repairs weren't done correctly.
0 Your vehicle or exhaust system had been
If you ever suspect exhaust is coming into
your vehicle:
0 Drive it only with all the windows down to
0 Have your vehicle fixed immediately.
modified
improperly.
blow
out any CO; and
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Running Your Engine While
You’re Parked
It’s better not to park with the engine running. But if
ever you have to, here
are some things to know.
A CAUTION:
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
L6BlizzardSS in the Index.)
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.
Don’t leave your vehicle when the engine is
running unless you have to.
If you’ve 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, always set your parking brake and
move the shift lever to PARK
(P).
Follow the proper steps to be sure your vehicle won’t
move. See “Shifting Into
PARK (P)” in the Index.
If you’re pulling a trailer, see “Towing a Trailer” in
the Index.
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Locking Rear Axle
Your locking rear axle can give you additional traction
on snow, mud, ice, sand or gravel.
It works like a
standard axle most
of the time, but when one of the rear
wheels has no traction and the other does, this feature
will allow the wheel with traction to move the vehicle.
Four-wheel Drive
Because your vehicle has four-wheel drive, you can
send your engine’s driving power to all four wheels for
extra traction.
To shift out of two-wheel drive and into
four-wheel drive, push the
4HI or 4LO button on the
transfer case switch. You should use
2HI for most
normal driving conditions.
Driving in the 4HI or 4LO positions for a long
time on dry
or wet pavement could shorten the
life
of your vehicle’s drivetrain.
Electronic Transfer Case
The transfer case switches
are above the radio controls.
Use
these switches to shift into and out of four-wheel
drive.
You can choose among three driving settings:
2HI: This setting is for driving in most street and
highway situations. Your front axle is not engaged in
two-wheel drive.
4HI: This setting engages your front axle to help drive
your vehicle. Use
4HI when you need extra traction,
such as on snowy or icy roads, or in most
off-road situations.
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4LO: This setting also engages your front axle to give
you extra traction. You may never need 4LO. It sends
the maximum power to all four wheels.
You might
choose 4LO if you were driving off-road in sand, mud
or deep snow and climbing or descending steep hills.
Indicator lights in the switches show
you which setting
you are in. The indicator lights will come on briefly
when you turn on the ignition and one will stay on.
If the lights do not come on, you should take your
vehicle in for service. An indicator light will flash
while shifting. It will remain illuminated when the
shift is completed.
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.
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.
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 kmh) 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 kmh). 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.
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 kdh) and the
transmission is in NEUTRAL
(N).
If your transfer case does not shift into 4L0, your
transmission indicator switch may require adjustment.
With your transmission in NEUTRAL (N), press and
release the 4LO switch. While the 4LO indicator light
is
flashing, shift your transmission into PARK (P). Wait
until the 4LO indicator light remains illuminated before
shifting your transmission into gear. This will get you
into 4L0, but you should take your vehicle in for service
to restore normal operation.
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