1998 GMC SIERRA torque

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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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).
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Front Position Rear Position
7. Lower the vehicle by rotating the ratchet
and wheel
wrench to the left. Lower the jack completely.
8. Tighten the nuts firmly
in a crisscross sequence
as shown by rotating
the wheel wrench
to
the right.
Incorrect wheel nuts
or improperly tightened
wheel nuts can cause the wheel to become loose
and even come
off. This could lead to an accident.
Be sure to use the correct wheel nuts.
If you have
to replace them, be sure to get new GM original
equipment wheel nuts.
Stop somewhere as soon as
you can and have the
nuts tightened with
a torque wrench to the
proper torque. See "Capacities and
Specifications"
in the Index.
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NOTICE:
Improperly tightened wheel nuts can lead to
brake pulsation and rotor damage.
To avoid
expensive brake repairs, evenly tighten the wheel
nuts in the proper sequence and to the proper
torque specification.
9. Put the wheel trim back on. For vehicles with plastic
wheel
nut caps, tighten the caps until they are
finger-tight, then tighten them an additional one-half
of a turn with the ratchet and wheel wrench.
Storing a Flat or Spare Tire and Tools
A CAUTION:
Storing a jack, a tire or other equipment in the
passenger compartment
of the vehicle could
cause injury. In
a sudden stop or collision, loose
equipment could strike someone. Store
all these
in the proper place.
Store the flat tire where the spare tire was stored.
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Some driving conditions or climates may cause a brake
squeal when the brakes are first applied or lightly
applied. This does
not mean something is wrong with
your brakes.
Properly torqued wheel
nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly torque wheel nuts
in the
proper sequence to
GM specifications.
If you have rear drum brakes, they don‘t have wear
indicators, but if you ever hear a rear brake rubbing
noise, have the rear brake linings inspected immediately. Also, the rear brake drums should be removed and
inspected each time the tires are removed for rotation
or
changing. When you have the front brake pads replaced,
have the rear brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
See “Brake System Inspection”
in Section 7 of this manual
under
Part C “Periodic Maintenance Inspections.”
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or
if there is a rapid increase in pedal
travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
If your brake pedal goes down farther than normal, your
rear drum brakes may need adjustment. Adjust them by
backing
up and firmly applying the brakes a few times.
Replacing Brake System Parts
The braking system on a modern vehicle is complex. Its
many parts have to be
of top quality and work well
together if the vehicle is to have really good braking.
Your vehicle was designed and tested
with top-quality
GM brake parts. When you replace parts of your braking
system
-- for example, when your brake linings wear
down and you have
to have new ones put in -- be sure
you get new approved
GM replacement parts. If you
don’t,
your brakes may no longer work properly. For
example,
if someone puts in brake linings that are wrong
for your vehicle, the balance between your front and
rear brakes can change
-- for the worse. The braking
performance you’ve come
to expect can change in many
other ways
if someone puts in the wrong replacement
brake parts.
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~ 11 your
vehicle has dual rear wheels and the load range
’ and tread design for your front tires is the same as your
rear tires, always use one of the correct rotation patterns
shown here when rotating your tires.
r.
If your vehicle has dual rear wheels and the load range
or tread design for your front tires is different from your
rear tires, always use the correct rotation pattern shown
here when rotating your tires. The dual tires are rotated
as a pair, and the inside rear tires become the outside
rear tires.
When you install dual wheels, be sure the vent holes in
the inner and outer wheels on each side are lined up.
After the tires have been rotated, adjust the front and
rear inflation pressures as shown
on the
Certificatioflire label. Make certain that all wheel nuts
are properly tightened. See “Wheel Nut Torque’’ in
the Index.
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You need a new tire if any of the following statements
are true:
0 You can see the indicators at three or more places
around the tire.
You can see cord or fabric showing through the
tire’s rubber.
The tread or sidewall is cracked, cut or snagged deep
enough to show cord or fabric.
The tire has a bump, bulge or split.
The tire has a puncture, cut or other damage that
can’t be repaired well because of the size or location
of the damage.
Dual Tire Operation
When the vehicle is new, or whenever a wheel, wheel
bolt or wheel
nut is replaced, check the wheel nut
torque after 100, 1,000 and 6’000 miles (160, 1 600 and
10 000 km) of driving. For proper torque, see “Wheel
Nut Torque”
in the Index. The outer
tire
on a dual wheel setup generally wears
Faster than the inner tire. Your tires will wear more
evenly and last longer if
you rotate the tires periodically.
If you’re going to be doing a lot
of driving on
high-crown roads,
you can reduce tire wear by adding
5 psi (35 kPa) to the tire pressure in the outer tires. Be
sure to return to the recommended pressures when
no
longer driving under those conditions. See “Changing a
Flat Tire’’ in the Index for more information.
If you operate your vehicle with a tire that is badly
underinflated, the tire can overheat. An overheated
tire can lose air suddenly or catch fire.
You or
others could be injured. Be sure all tires (including
the spare,
if any) are properly inflated.
Buying New Tires
To find out what kind and size of tires you need, look at
the CertificatiodTire label.
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Whenever a wheel, wheel bolt or wheel nut is replaced
on
a dual wheel setup, check the wheel nut torque after
100, 1,000 and 6,000 miles ( 160, 1 600 and 10 000 km)
of driving. For proper torque, see “Wheel Nut Torque’’
in the Index.
See “Changing
a Flat Tire” in the Index for
more information.
Used Replacement Wheels
/!1 CAUTION:
Putting a used wheel on your vehicle is
dangerous.
You can’t know how it’s been used or
how
far it’s been driven. It could fail suddenly
and cause an accident. If
you have to replace a
wheel, use a new GM original equipment wheel.
Tire Chains
NOTICE:
If your vehicle has dual wheels, P265/75R16 or
LT265/75R16 size tires, don’t use tire chains.
They can damage your vehicle because there’s
not enough clearance.
Use another type of traction device only
if its
manufacturer recommends it for
use on your
vehicle and tire size combination and road
conditions.
Follow that manufacturer’s
instructions. To help avoid damage to your
vehicle, drive slowly, readjust or remove the
device
if it’s contacting your vehicle, and don’t
spin your wheels.
If you do find traction devices that will fit, install
them on the rear tires.
NOTICE: (Continued)
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