2001 GMC ENVOY manual transmission

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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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4HI: Use 4HI when you need extra traction, such as
on snowy or icy roads or in most off
-road situations.
This setting also engages your front axle to help drive
your vehicle.
4LO: This setting also engages your front axle and
delivers extra torque. You may never need 4LO. It sends
maximum power to all four wheels. You might choose
4LO if you are driving off
-road in deep sand, deep mud,
deep snow and climbing or descending steep hills.
CAUTION:
Shifting the transfer case to NEUTRAL can cause
your vehicle to roll even if the transmission is in
PARK (P), or if you have a manual transmission,
even if you are in gear. You or someone else could
be seriously injured. Be sure to set the parking
brake before placing the transfer case in
NEUTRAL. See ªParking Brakeº in the Index.
NEUTRAL: Shift the vehicle's transfer case to
NEUTRAL only when towing your vehicle. See
ªRecreational Vehicle Towingº or ªTowing Your
Vehicleº in the Index for more information.
Indicator lights in the switches show 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
to your dealer for service. An indicator light will
flash while shifting the transfer case. It will remain
illuminated when the shift is complete. If for some
reason the transfer case cannot make a requested shift,
it will return to the last chosen setting.
If the SERVICE 4WD light stays on, you should take
your vehicle to your dealer for service. See ªService
4WDº in the Index for further information.
Shifting to 4HI or AUTO 4WD
Press and release the 4HI or AUTO 4WD switch.
This can be done at any speed, and the indicator light
will flash while shifting. It will remain illuminated when
the shift is complete.
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Shifting to 2HI
Press and release the 2HI switch. This can be done at
any speed.
Shifting to 4LO
To shift to 4LO, the vehicle's engine must be running
and the vehicle must be stopped or moving less
than 3 mph (4.8 km/h) with the transmission in
NEUTRAL (N) or with the clutch pedal pressed
for vehicles with manual transmission. The preferred
method for shifting into 4LO is to have your vehicle
moving 1 or 2 mph (1.6 to 3.2 km/h). Press and
release the 4LO switch. You must wait for the4LO
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 less than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N) or with the clutch
pedal pressed for vehicles with manual transmission.
After 30 seconds, the transfer case will return to the
setting last chosen.Shifting Out of 4LO
To shift from 4LO to 4HI, AUTO 4WD or 2HI, your
vehicle must be stopped or moving less than 3 mph
(4.8 km/h) with the transmission in NEUTRAL (N),
or with the clutch pedal pressed for vehicles with manual
transmission, and the engine running. The preferred
method for shifting out of 4LO is to have your vehicle
moving 1 or 2 mph (1.6 to 3.2 km/h). Press and release
the 4HI, AUTO 4WD or 2HI switch. You must wait for
the 4HI, AUTO 4WD or 2HI indicator light to stop
flashing and remain illuminated before shifting your
transmission into gear.
If the 4HI, AUTO 4WD or 2HI switch is pressed when
your vehicle is in gear and/or moving, the 4HI, AUTO
4WD or 2HI indicator light will flash for 30 seconds but
will not complete the shift unless your vehicle is moving
less than 3mph (4.8 km/h) with the transmission in
NEUTRAL (N) or with the clutch pedal pressed for
vehicles with manual transmission.
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Shifting to NEUTRAL
To shift the transfer case to NEUTRAL, first make sure
the vehicle is parked so that it will not roll:
1. Set the parking brake.
2. Start the vehicle.
3. Connect the vehicle to the towing vehicle.
4. Put the transmission in NEUTRAL (N) or
have the clutch pedal pressed for vehicles with
manual transmission.
5. Shift the transfer case to 2HI.
6. Simultaneously press and hold the 2HI and 4LO
buttons for 10 seconds. The NEUTRAL light will
come on when the transfer case shift to NEUTRAL
is complete.
7. Shift the transmission to REVERSE (R) for one
second, then shift the transmission to DRIVE (D)
for one second or FIRST (1) for vehicles with
manual transmission.
8. Turn the ignition to OFF.
9. Place the transmission shift lever in PARK (P) or
FIRST (1) for vehicles with manual transmission.
10. Release the parking brake prior to towing.Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Set the parking brake and apply the regular
brake pedal.
2. Start the vehicle with the transmission in PARK (P)
or FIRST (1) for vehicles with manual transmission.
3. Press the button for the desired transfer case position
(2HI, 4HI, AUTO 4WD or 4LO).
4. Put the transmission in NEUTRAL (N) or press the
clutch pedal for vehicles with manual transmission.
5. Shift the transmission lever to the desired position.
After the transfer case has shifted out of NEUTRAL,
the NEUTRAL light will go out.
6. A re
-engagement sound is normal when shifting out
of NEUTRAL.
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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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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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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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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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