1999 CHEVROLET SUBURBAN transmission

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The transfer case shift lever is on the floor to the right of
the driver. Use this lever to shift into and out of
four
-wheel drive.
The front axle portion of the indicator diagram will light
up when you shift into four
-wheel drive and the front
axle engages.
Some delay between shifting and the indicator's lighting
is normal. If the front axle light does not go out
immediately after you shift out of four
-wheel drive,
have your dealer check your system.
An indicator near the lever shows you the transfer
case settings: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 and in most off
-road situations.
CAUTION:
Shifting the transfer case to NEUTRAL (N) can
cause your vehicle to roll even if the transmission
is in PARK (P). You or someone else could be
seriously injured. Be sure to set the parking
brake before placing the transfer case in
NEUTRAL (N). See ªParking Brakeº in
the Index.

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NEUTRAL (N): Shift to this setting only when
your vehicle needs to be towed or when using a
power take
-off.
4
-Wheel Low (4L): This setting also engages your
front axle to give you extra power and also gives you a
higher driveline ratio. It should be used only for
off
-road driving.
You can shift from 2
-Wheel High (2H) to 4-Wheel
High (4H) or from 4
-Wheel High (4H) to 2-Wheel
High (2H) while the vehicle is moving. Your front axle
will engage faster if you take your foot off 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 into 4
-Wheel High (4H).To shift into or out of 4
-Wheel Low (4L) or
NEUTRAL (N):
1. Slow the vehicle to a roll, about 1 to 3 mph
(2 to 5 km/h) and shift the transmission into
NEUTRAL (N).
2. Shift the transfer case shift lever in one
continuous motion.
Don't pause in NEUTRAL (N) as you shift the transfer
case into 4
-Wheel Low (4L), or your gears could clash.
Remember that driving in 4
-Wheel High (4H) or
4
-Wheel Low (4L) may reduce fuel economy. Also,
driving in four
-wheel drive on dry pavement could
cause your tires to wear faster and make your transfer
case harder to shift and run noisier.
When your headlamps or parking lamps are on, rotate the
thumbwheel next to the headlamp switch up to brighten or
down to dim your transfer case indicator light.

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CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the transmission
is in PARK (P). 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 completed.
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). 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.
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). After 30 seconds the
transfer case will return to the setting last chosen.

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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) and
the engine running. 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, 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 3 mph (4.8 km/h) and the transmission is in
NEUTRAL (N).
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).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 AUTOMATIC
OVERDRIVE
for one second.
8. Turn the ignition to OFF.
9. Place the transmission shift lever in PARK (P).
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).
3. Press the button for the desired transfer case shift
position (2HI, 4HI, AUTO 4WD or 4LO).
4. Put the transmission in NEUTRAL (N).
5. Shift the transmission lever to the desired position.
After the transfer case has shifted out of NEUTRAL,
the light will go out.

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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
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).
Shifting Out of PARK (P)
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 ªAutomatic Transmissionº 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 into the 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 the OFF ignition position.
2. Apply and hold the brake until the end of Step 4.
3. Shift the vehicle to NEUTRAL (N).
4. Start the vehicle and then 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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3. Decide which one of the three channels you want to
program. Using both hands, press the hand
-held
transmitter button and the desired button on the
universal transmitter. Continue to hold both buttons
through Step 4.
4. Hold down both buttons until you see the red light
on the universal transmitter flash rapidly. The rapid
flashing, which could take up to 90 seconds,
indicates that the universal transmitter has been
programmed. Release both buttons once the light
starts flashing rapidly.
If you have trouble programming the universal
transmitter, make sure that you have followed the
directions exactly as described and that the battery in the
hand
-held transmitter is not dead. If you still cannot
program it, rotate the hand
-held transmitter end over end
and try again. The universal transmitter may not work
with older garage door openers that do not meet current
Federal Consumer Safety Standards. If you cannot
program the transmitter after repeated attempts, consult
your GM dealer.
Be sure to keep the original hand
-held transmitter
in case you need to erase and reprogram the
universal transmitter.
Operating the Transmitter
Press and hold the appropriate button on the universal
transmitter. The red light comes on while the signal is
being transmitted.
Note that the effective transmission range of the
universal transmitter may differ from the hand
-held
transmitter and from one channel to another.
Erasing Channels
To erase all three programmed channels, hold down the
two outside buttons until the red light begins to flash.
Individual channels cannot be erased, but can be
reprogrammed using the procedure for programming the
transmitter explained earlier.
Training a Garage Opener with a ªRolling
Codeº Feature
If you programmed the universal transmitter, but the
garage door will not open, and if your garage door
opener was manufactured after 1995, your garage door
may have a security feature that changes the ªcodeº of
your garage door opener every time it is opened
or closed.

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NOTICE:
If you keep driving your vehicle with this light
on, after a while, your emission controls may not
work as well, your fuel economy may not be as
good and your engine may not run as smoothly.
This could lead to costly repairs that may not be
covered by your warranty.
NOTICE:
Modifications made to the engine, transmission,
exhaust or fuel system of your vehicle or the
replacement of the original tires with other than
those of the same Tire Performance Criteria
(TPC) can affect your vehicle's emission controls
and may cause the SERVICE ENGINE SOON
light to come on. Modifications to these systems
could lead to costly repairs not covered by your
warranty. This may also result in a failure to pass
a required Emission Inspection/Maintenance test.
This light should come on, as a check to show you it is
working, when the ignition is on and the engine is not
running. If the light doesn't come on, have it repaired.
This light will also come on during a malfunction in one
of two ways:

Light Flashing
-- A misfire condition has been
detected. A misfire increases vehicle emissions and
may damage the emission control system on your
vehicle. Dealer or qualified service center diagnosis
and service may be required.

Light On Steady
-- An emission control system
malfunction has been detected on your vehicle.
Dealer or qualified service center diagnosis and
service may be required.
If the Light Is Flashing
The following may prevent more serious damage to
your vehicle:

Reducing vehicle speed.

Avoiding hard accelerations.

Avoiding steep uphill grades.

If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.

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Ease up on your speed as you approach the top of
the hill.

Attach a flag to the vehicle to make you more visible
to approaching traffic on trails or hills.

Sound the horn as you approach the top of the hill to
let opposing traffic know you're there.

Use your headlamps even during the day. They make
you more visible to oncoming traffic.
CAUTION:
Driving to the top (crest) of a hill at full speed can
cause an accident. There could be a drop
-off,
embankment, cliff, or even another vehicle. You
could be seriously injured or killed. As you near
the top of a hill, slow down and stay alert.
Q:What should I do if my vehicle stalls, or is about
to stall, and I can't make it up the hill?
A:If this happens, there are some things you should
do, and there are some things you must not do.
First, here's what you should do:

Push the brake pedal to stop the vehicle and keep it
from rolling backwards. Also, apply the parking brake.

If your engine is still running, shift the transmission
to REVERSE (R), release the parking brake, and
slowly back down the hill in REVERSE (R).

If your engine has stopped running, you'll need to
restart it. With the brake pedal pressed and the
parking brake still applied, shift the transmission to
PARK (P) and restart the engine. Then, shift to
REVERSE (R), release the parking brake, and
slowly back down the hill as straight as possible in
REVERSE (R).