transmission GMC SIERRA 1998 User Guide

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
2-20
ProCarManuals.com

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.
2-22
ProCarManuals.com

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.
2-23
ProCarManuals.com

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.
2-24
ProCarManuals.com

Shifting from 4LO to 4HI or 2HI
To shift from 4LO to 4HI or 2H1, your 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 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.
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 will not complete the shift unless the
vehicle is moving slower than
3 mph (4.8 km/h) and the
transmission is in
NEUTRAL (N).
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 lever, located
just above the parking
brake pedal, marked
BRAISE RELEASE.
If the ignition is on when the parking brake is released,
the brake system warning light will go off.
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. Always check to be sure
your parking brake is fully released before
you drive.
2-25
ProCarManuals.com

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.
2-26
ProCarManuals.com

Leaving Your Vehicle With the Engine
Running (Automatic Transmission
Only)
I A CATJTION:
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 with
a manual transfer case
shift lever 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). 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 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 (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 “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).
2-28
ProCarManuals.com

Shifting Out of PARK (P)
(Automatic Transmission)
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 “Automatic Transmission” 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
to any 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 OFF.
2. Apply and hold the brake until the end of Step 4.
3. Shift to NEUTRAL (N).
4. Start the vehicle and shift to the drive gear you want.
5. Have the brake-transmission shift interlock system
fixed as
soon as you can.
Parking Your Vehicle
(Manual Transmission Models
Only)
Before you get out of your vehicle, put your manual
transmission in REVERSE
(R), turn off the engine, and
firmly apply the parking brake.
If you have four-wheel drive, be sure your transfer case
is in a drive gear. Your vehicle could roll if it isn’t.
If
you are parking on a hill, or if you are pulling a
trailer, see “Towing a Trailer” in
the Index.
2-29
ProCarManuals.com

Speedometer and Odometer
Your speedometer lets you see your speed in both miles
per hour (mphj and kilometers per hour (km/hj. Your
odometer shows how far your vehicle has been driven,
in either miles (used
in the United States) or kilometers
(used
in Canada).
Tamper-Resistant Odometer
Your odometer is tamper-resistant. The odometer will
show silver lines between the numbers if someone tries
to turn it back.
You may wonder what happens if your vehicle needs a
new odometer installed. If the new odometer can be set
to the mileage total of
the old odometer, then it must be.
But if
it can’t, then it’s set at zero, and a label must be
put on the driver‘s door to show
the old mileage reading
when
the new odometer was installed.
Trip Odometer
The trip odometer can tell you how far your vehicle has
been driven since you last set the trip odometer to zero.
To reset the trip odometer, fully press the reset button
located near the trip odometer readout.
If the reset
button is not
fully pressed, the trip odometer may not go
all the way back to zero. If it doesn’t, you may have to
press the reset button again
to reset the readout to zero.
Tachometer
Your tachometer displays the engine speed in
revolutions per minute (rpmj.
NOTICE:
On vehicles with a manual transmission, if you
operate the engine with the tachometer in the red
area, your engine or other parts could be damaged.
Damage to your engine or vehicle caused by
operating the engine in the red area isn’t covered
by your vehicle warranty. Don’t operate the
engine with the tachometer in the red area.
2-63
ProCarManuals.com

Security Light
SECURITY
This light will come on
briefly when you turn the
key to
START.
The light will stay on until the engme starts. If the light
flashes, the Passlock@ System has entered a tamper
mode. If the vehicle fails
to start, see “Passlock” in
the Index.
If the light comes on continuously while driving and
stays
on, there may be a problem with the Passlock
System. Your vehicle will
not be protected by Passlock,
and you should see your
GM dealer.
Up Shift Light (If Equipped)
This light is used on
some models with
manual transmissions.
The
SHIFT indicator light will help you get the best fuel
economy. See ‘(Shift Light” or ;’Shift Speeds”
in this
section for more information.
2-73
ProCarManuals.com