wheel GMC SIERRA 1998 User Guide

Automatic Transmission Operation
I
There are several different positions for your shift lever.
If your vehicle is equipped with an automatic
transmission, it now features an electronic shift position
indicator within the instrument cluster. This display
must be powered anytime the shift lever is capable of
being moved out of
PARK (P). This means that if your
key is
in OFF, rather than LOCK, there will be a small
current drain on your battery which could discharge
your battery over a period
of time. If you have to leave
your key in the ignition in
OFF for an extended period,
it is recommended that you disconnect the battery cable
from the battery
to prevent discharging your battery.
PARK
(P): This locks your rear wheels. It’s the best
position to use when you start your engine because your
vehicle can’t move easily. It
is 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 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, 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
(N). So, be sure the transfer case is in
a drive gear, two-wheel high (2H) or four-wheel
high
(4H) or four-wheel low (4L) -- not in
NEUTRAL (N). 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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REVERSE (R): Use this gear to back up.
I 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
"Stuck: In Sand, Mud, Ice or Snow" 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 (Nj only. Also, use
NEUTRAL (N) when your vehicle is being towed.
' A CAUTION:
Shifting out of PARK (P) or NEUTRAL (N) while
your engine
is "racing" (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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AUTOMATIC OVERDRIVE (@): This position is
for normal driving.
If you need more power for passing,
and you’re:
Going less than about 35 mph (56 kndh), push your
accelerator pedal about halfway down.
0 Going about 35 rnph (56 kndh) or more. push the
accelerator
all the way down.
You’ll shift down to the next gear and have more power.
AUTOMATIC OVERDRIVE
(@) can be used when
towing
a trailer. carrying a heavy load, driving on steep
hills or for off-road driving. You may want
to shif’t the
transmission to
THIRD (3) or. if necessary, a lower gear
selection
if the transmission shifts too often.
THIRD (3): This position is also used for norrnal
driving, however
it offers more power and lower fuel
economy than AUTOMATIC OVERDRIVE
(@).
SECOND (2): This position gives you more power but
lower fuel economy. You can use SECOND (2) on hills.
It can help control your speed as you go clown steep
mountain
roads, but then you would also want to use
your brakes off and on.
If you manually select SECOND (2), the transmission will
drive
in second gear. You may use this feature for reducing
torque to the
rex wheels when you are trying to start your
vehicle from
a stop on slippery road surfaces.
FIRST (1): This position gives you even Inore power
(but lower fuel economy) than SECOND (2). You can
LIS~ it on very steep hills, or in deep snow or mud. If the
selector lever is put
in FIRST (1 j while the vehicle is
moving forward, the transmission won’t shift into first
E war 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.
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NOTICE:
Up Shift Light
4l
If you have a manual
Shift to REVERSE (R) only after your vehicle is transmission, you may have
a SHIFT light. This light
stopped. Shifting to REVERSE (R) while your
vehicle is moving could damage your transmission. will show you when to shift
best fuel economy.
to the next higher gear for
SHIFT
AI - - , use REVERSE (R), along with the parking brake,
when turning
off your engine and parking your vehicle.
Shift Speeds
I JOU skip more than one gear when you
downshift, you could lose control
of your vehicle.
And you could injure yourself or others. Don’t shift
down more than one gear when you downshift.
If your speed drops below 20 mph (32 kmh), or if the
engine
is not running smoothly, you should downshift to
the next lower gear. You may have to downshift two or
more gears to keep the engine running smoothly or for
good performance. When
this light comes on,
you can shift to the next
higher gear if weather, road and traffic conditions let
you. For the best fuel economy, accelerate slowly and
shift when the light comes on.
While
you accelerate, it is normal for the light to go on
and
off if you quickly change the position of the
accelerator. Ignore the
SHIFT light when you downshift.
If your vehicle has four-wheel drive and
is equipped
with a manual transmission, disregard the SHIFT light
when
the transfer case is in 4-Wheel Low.
I
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Four-wheel Drive (If Equipped)
If your vehicle has four-wheel drive, you can send your
engine’s driving power to all four wheels for
extra
traction. To get the most satisfaction out of four-wheel
drive, you must be familiar with its operation. Read the
part that follows before using four-wheel drive. You
should use
2-WHEEL HIGH (2H) for most normal
driving conditions.
I i
I NOTICE:
Driving in the 4-WHEEL HIGH (4H) or
4-WHEEL LOW (4L) positions for a long time
on dry or wet pavement could shorten the life
of
your vehicle’s drivetrain.
Front Axle Locking Feature
The front axle locks and unlocks automatically when you
shift the transfer case. Some delay for the axle to lock or
unlock is normal.
If the outside temperature is very hot, or
the vehicle has been used under hard driving conditions,
there may
be a slight delay for the axle to unlock.
Manual Transfer Case (If Equipped)
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.
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I ~ 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,
1 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.
Shifting the transfer case to
NEUTRAL (N) 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 (N). See “Parking
Brake” in the Index.
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.
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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 an automatic transmission
into NEUTRAL
(N), or with a manual transmission,
press the clutch pedal.
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
thumb wheel next
to the headlamp switch up to brighten
or down to dim your transfer case indicator light.
Electronic Transfer Case (If Equipped)
If your four-wheel-drive vehicle has the electronic
transfer case,
the transfer case switches are below and to
the left of the climate control system.
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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.
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 the last chosen setting 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. If for some reason the transfer cannot make a
requested shift, it will return
to the last chosen setting.
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.
ting from 2HI or 4HI to 4LO
'li hift 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 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 kmh) and the
transmission is
in NEUTRAL (N). After 30 seconds the
transfer case will return to 4HI.
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If you are towing a trailer and are parking on any 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) (Automatic
Transmission Only)
If you have a 3500 HD model, it is recommended that
the propshaft mounted parking brake be burnished
as
part of the new vehicle break-in. The parking brake
will work best after
it has been burnished following
these instructions.
Make
10 stops, using the parking brake foot pedal, from
20 mph (32 kmh) about 2 1/2 miles (4 km) apart. In
between stops, drive the vehicle at
20 mph (32 km/h).
A 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.
If
you have fourwheel 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.
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1.
2.
Hold the brake pedal down with your right foot and
set the parking brake.
Move
the shift lever into PARK (P) position like this:
r
3.
Pull the lever toward you.
4.
5.
Move the lever up as far as it will go.
If you have four-wheel drive, be sure the transfer
case is in a drive gear
-- not in NEUTRAL (N).
Turn the ignition key to LOCK.
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).
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