2001 GMC ENVOY automatic transmission

2-27
Ensure the shift lever is fully in PARK (P) before
starting the engine. Your vehicle has an automatic
transmission shift lock control system. You have to
fully apply your regular brakes before you can shift
from PARK (P) when the ignition key is in RUN. If you
cannot shift out of PARK (P), ease pressure on the shift
lever
-- push the shift lever all the way into PARK (P)
(press the button in on the console shift lever) as you
maintain brake application. Then move the shift lever
into the gear you wish. See ªShifting Out of PARK (P)º
in the Index.
REVERSE (R): Use this gear to back up.
NOTICE:
Shifting to REVERSE (R) while your vehicle is
moving forward could damage your transmission.
Shift to REVERSE (R) only after your vehicle
is stopped.
To rock your vehicle back and forth to get out of snow,
ice or sand without damaging your transmission, see
ªStuck In Sand, Mud, Ice or Snowº in the Index.NEUTRAL (N): In this position, your engine doesn't
connect with the wheels. To restart when you're already
moving, use NEUTRAL (N) only.
CAUTION:
Shifting out of PARK (P) or NEUTRAL (N) while
your engine is ªracingº (running at high speed)
is dangerous. Unless your foot is firmly on the
brake pedal, your vehicle could move very
rapidly. You could lose control and hit people
or objects. Don't shift out of PARK (P) or
NEUTRAL (N) while your engine is racing.
NOTICE:
Damage to your transmission caused by shifting
out of PARK (P) or NEUTRAL (N) with the
engine racing isn't covered by your warranty.
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2-32
Electronic Transfer Case (If Equipped)
If your four-wheel-drive
vehicle has the electronic
transfer case, the transfer
case switches are to the
right of the steering wheel
on the instrument panel.
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. When this lamp is lit, it is about
one
-half as bright as the others.
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.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 4LO, the vehicle must be
stopped or moving less than 3 mph (4.8 km/h) with
the transmission in NEUTRAL (N) in vehicles equipped
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2-33
with an automatic transmission or the clutch pedal
engaged in vehicles equipped with a manual
transmission. 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 or releasing the clutch pedal.
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) or the clutch
pedal engaged.
On automatic transmission equipped vehicles, if your
transfer case does not shift into 4LO, 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 4LO,
but you should take your vehicle in for service to restore
normal operation.Shifting from 4LO to 4HI or 2HI
To shift from 4LO to 4HI or 2HI, your vehicle must
be stopped or moving less than 3 mph (4.8 km/h) with
the transmission in NEUTRAL (N) or the clutch pedal
engaged. 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 or releasing the clutch pedal.
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 not complete the shift unless the
vehicle is moving slower than 3 mph (4.8 km/h) and
the transmission is in NEUTRAL (N) or the clutch
pedal engaged.
On automatic transmission equipped vehicles, if your
transfer case does not shift into 4HI, your transmission
indicator switch may require adjustment. With your
transmission in NEUTRAL (N), press and release the
4HI switch. While the 4HI indicator light is flashing,
shift your transmission into PARK (P). Wait until the
4HI indicator light remains illuminated before shifting
your transmission into gear. This will get you into 4HI,
but you should take your vehicle in for service to restore
normal operation.
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2-39
Shifting Into PARK (P)
(Automatic Transmission Only)
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 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. With four
-wheel drive, your
vehicle will be free to roll
-- even if your shift
lever is in PARK (P)
-- if your transfer case is in
NEUTRAL. So be sure the transfer case is in a
drive gear
-- not in NEUTRAL. See ªFour-Wheel
Drive (Automatic Transfer Case)º in the Index.
Always put the shift lever fully in PARK (P) with
the parking brake firmly set. If you're pulling a
trailer, see ªTowing a Trailerº in the Index.
Column Shift Lever
1. Hold the brake pedal down with your right foot and
set the parking brake.
2. Move the shift lever into PARK (P) like this:

Pull the lever toward you.
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2-42
Leaving Your Vehicle With the Engine
Running (Automatic Transmission Only)
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, your vehicle will be free to
roll
-- even if your shift lever is in PARK (P) -- if
your transfer case is in NEUTRAL. So be sure
the transfer case is in a drive gear
-- not in
NEUTRAL. See ªFour
-Wheel Drive (Automatic
Transfer Case)º in the Index. 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 first pulling
it toward you (or pressing the button on a console shift
lever). 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 ªtorque lock.º
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 ªShifting Into
PARK (P)º 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).
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2-43
Shifting Out of PARK (P)
(Automatic Transmission Only)
Your vehicle has an automatic transmission shift lock
control system. You have to fully apply the regular
brakes before you can shift from PARK (P) when the
ignition is in RUN. See ªAutomatic Transmission
Operationº 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 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 the transmission to NEUTRAL (N).
4. Start the vehicle and then shift to the drive gear
you want.
5. Have the vehicle fixed as soon as possible.
Parking Your Vehicle (Manual
Transmission Models Only)
Before you get out of your vehicle, move the shift
lever into REVERSE (R), and firmly apply the
parking brake. Once the shift lever has been placed into
REVERSE (R) with the clutch pedal pressed in, you can
turn the ignition key to OFF, remove the key and release
the clutch.
If you are parking on a hill, or if your vehicle is pulling
a trailer, see ªTowing a Trailerº in the Index.
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2-45
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.
CAUTION:
Idling the engine with the climate control
system off could allow dangerous exhaust into
your vehicle. See the earlier Caution under
ªEngine Exhaust.º
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 ªBlizzardº in the Index.
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 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).
If you have four-wheel drive, your vehicle
will be free to roll
-- even if your shift lever
is in PARK (P)
-- if your transfer case is in
NEUTRAL. So be sure the transfer case is in a
drive gear
-- not in NEUTRAL. See ªFour-Wheel
Drive (Automatic Transfer Case)º in the Index.
Follow the proper steps to be sure your vehicle won't
move. See ªShifting Into PARK (P)º in the Index.
If you're pulling a trailer, see ªTowing a Trailerº in
the Index.
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2-50
Rear Window Washer/Wiper
This switch is located on
the instrument panel to the
right of the steering wheel.
To turn the rear wiper on, slide the switch to either
LO or HI. For delayed wiping, slide the switch to LO.
For steady wiping, slide the switch to HI. To turn the
wiper off, slide the switch to OFF.
To wash the window, press the wash button located on
the switch. The switch must be in either LO or HI.
The rear window washer uses the same fluid bottle
as the windshield washer. However, the rear window
washer will run out of fluid before the windshield
washer. If you can wash your windshield but not
your rear window, check your fluid level.
Cruise Control (If Equipped)
With cruise control, you can
maintain a speed of about
25 mph (40 km/h) or more
without keeping your foot
on the accelerator. This can
really help on long trips.
Cruise control does not
work at speeds below
about 25 mph (40 km/h).
If you have an automatic transmission and you apply
your brakes, the cruise control will shut off.
If you have a manual transmission and you apply
your brakes or push the clutch pedal, the cruise control
will shut off.
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