1998 GMC SIERRA wheel

Driving On Grades
Reduce speed and shift to a lower gear before you start
down a long or steep downgrade. If
you don’t shift
down,
you might have to use your brakes so much that
they would
get hot and no longer work well.
On a long uphill grade, shift down and reduce your
speed
to around 45 mph (70 kdh) to reduce the
possibility
of engine and transmission overheating.
If you have an automatic transmission, you can tow in
AUTOMATIC OVERDRIVE
(@). You may want to
shift the transmission
to THIRD (3) or, if necessary, a
lower gear selection
if the transmission shifts too often
(e.g., under heavy loads and/or hilly conditions).
If
you have a manual transmission and you are towing a
trailer, it’s better not to
use FIFTH (5) gear. Just drive in
FOURTH
(4) gear (or, as you need to, a lower gear).
When towing at high altitude
on steep uphill grades,
consider the following: Engine coolant
will boil at a
lower temperature than at normal altitudes. If you turn
your engine off immediately after towing
at high altitude
on steep uphill grades, your vehicle may show signs
similar to engine overheating. To avoid this, let the
engine run while parked (preferably on level ground) with
the automatic transmission in
PARK (P) (or the
manual transmission out of gear and the parking brake
applied) for a few minutes before turning the engine
off.
If you do get the overheat warning, see “Engine
Overheating’’ in
the Index.
Parking on Hills
You really should not park your vehicle, with a trailer
attached, on a
hill. If something goes wrong, your rig
could start to move. People can be injured, and both
your vehicle and the trailer can be damaged.
But
if you ever have to park your rig on a hill, here’s
how to do it:
1.
2.
3.
4.
Apply your regular brakes, but don’t shift into
PARK
(P) yet for an automatic transmission, or into
gear for a manual transmission.
Have someone place chocks under the trailer wheels.
When the wheel chocks are
in place, release the
regular brakes until the chocks absorb the load.
Reapply the regular brakes. Then apply your parking brake and
shift into PARK (P) for an automatic
transmission, or REVERSE (R)
for a manual
transmission.
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5. If you have a four-wheel-drive vehicle,
be sure the transfer case is in
a drive gear and not
in
NEUTRAL (N).
6. Release the regular brakes.
-
/r CAUTIOIA:
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 four-wheel 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).
When You Are Ready to Leave After
Parking
on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
Start your engine;
Shift into a gear; and
Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly
until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling
a trailer. See the Maintenance Schedule for more
on this. Things that are especially important
in trailer
operation are automatic transmission fluid (don’t
overfill), engine
oil, axle lubricant, belt, cooling system
and brake adjustment. Each of these is covered in this
manual, and the Index will help you find them quickly.
If you’re trailering, it’s a good idea to review these
sections before
you start your trip.
Check periodically
to see that all hitch nuts and bolts
are tight.
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Power Winches
If you wish to use a power winch on your vehicle, only
use
it when your vehicle is stationary or anchored.
I NOTICE:
Using a power winch with the transmission in
gear may damage the transmission. When
operating
a power winch, always leave the
transmission in NEUTRAL
(N).
Use the regular brakes, set the parking brake, or block
the wheels
to keep your vehicle from rolling.
Power Take-Off (PTO)
(Manual Transmission)
NOTICE:
If you have a PTO that will exceed 35 hp installed
on your vehicle, it could damage the transfer case
or transmission. When having
a PTO installed on
your vehicle, make sure that it will not exceed
35 hp.
Before using
a PTO, refer to the manufacturer’s or
installer’s instructions.
I NOTICE:
Using a PTO while operating in one place before
the vehicle has reached normal operating
temperature can damage the transfer case or
transmission. If you
will be using the PTO while
operating in one place, drive and warm up the
vehicle before using the PTO.
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To engage a PTO:
1. Hold the clutch pedal down.
2. Set the parking brake.
3. Shift the transmission into NEUTRAL (N).
4. Engage the PTO.
NOTICE:
Using a PTO for more than four hours without
driving your vehicle can damage the transfer case
or transmission. If using a
PTO for more than
four hours without driving your vehicle, drive
your vehicle for a while to allow the transfer case
and transmission to cool.
If you are going to drive the vehicle, shift the
transfer case into the range you want
(if you have
four-wheel drive). Then shift
the transmission into
the gear you want, apply the regular brakes and
release the parking brake.
5. Release the clutch (and the regular brakes) as you
normally would. When
you release the clutch, the
PTO will start.
To engage a PTO while the vehicle is moving:
1. Hold the clutch pedal down.
2. Shift the transmission into NEUTRAL (N).
3. Engage the PTO.
4. Shift the transmission into the gear you want.
5. Release the clutch as you normally would. When you
release the clutch, the
PTO will start.
Using a Transfer Case Mounted Power
Take-Off (Manual Transmission)
1.
2.
3.
4.
5.
6.
Hold the clutch pedal down.
Set the parking brake.
Shift
the transfer case into NEUTRAL (N).
If the vehicle will remain in the same place, shift the
transmission into
the highest gear.
Engage the PTO.
If you are going to drive the vehicle, shift the
transmission into the gear you want. Then shift the
transfer case into the range you want, apply the
regular brakes and release the parking brake.
Release the clutch (and the regular brakes) as
you
normally would. When you release the clutch, the
PTO will start.
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2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren’t touching
each other. If they are, it could cause a ground
connection
you don’t want. You wouldn’t be able
to start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility
of the vehicles rolling, set
the parking brake firmly on both vehicles involved
in the jump start procedure. Put an automatic
transmission in
PARK (P) or a manual transmission
in NEUTRAL (N).
If you have a four-wheel-drive
vehicle, be sure the transfer case is not in
NEUTRAL
(N).
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or accessory power outlets. Turn
off all lamps
that aren’t needed as well as radios. This will avoid
sparks and help save both batteries. In addition, it
could save your radio!
I NOTICE:
If you leave your radio on, it could be badly
damaged. The repairs wouldn’t be covered by
your warranty.
4. Open the hoods and locate the batteries. Find the
positive
(+) and negative (-) terminals on each battery.
If your vehicle has air conditioning, the auxiliary
electric fan under the hood can start up even
when the engine is not running and can injure
you. Keep hands, clothing and tools
away from
any underhood electric fan.
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11. Try to start the vehicle with the dead battery.
If it won’t start after
a few tries, it probably
needs service.
12. Remove the cables in reverse order to prevent
electrical shorting. Take care that they don’t touch
each other or any other metal.
A. Heavy Metal Engine Part
B. Good Battery
C. Dead Battery
Towing Your Vehicle
Try to have your GM dealer or a professional towing
service tow your vehicle. See “Roadside Assistance’’
in
the Index.
If your vehicle has been changed since it was
factory-new, by adding such things
as fog lamps, aero
skirting, or special tires and wheels, these instructions
may not be correct.
Before you do anything, turn on the hazard
warning flashers.
When you call, tell the towing service:
0 That your vehicle has rear-wheel-drive, or that it has
the four-wheel-drive option.
0 The make, model and year of your vehicle.
Whether you can move the shift lever for the
0 If there was an accident, what was damaged.
When
the towing service arrives, let the tow operator
know that this manual contains detailed towing
instructions and illustrations. The operator may want to
see
them.
transmission and transfer case, if you have one.
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A CAUTION:
To help avoid injury to you or others:
0
0
0
0
0
a
0
Never let passengers ride in a vehicle that is
being towed. Never tow faster than safe or posted speeds.
Never tow with damaged parts not
fully secured.
Never get under your vehicle after it has
been lifted by the tow truck.
Always use separate safety chains on each
side when towing a vehicle.
For pickups (except cab chassis models),
use T-hooks on front of vehicle, J-hooks
on rear.
For cab chassis models, use J-hooks on
front and rear of vehicle.
A CAUTION:
A vehicle can fall from a car carrier if it isn’t
adequately secured. This can cause a collision,
serious personal injury and vehicle damage. The
vehicle should be tightly secured with chains or
steel cables before it is transported.
Don’t use substitutes (ropes, leather straps,
canvas webbing, etc.) that can be cut by sharp
edges underneath the towed vehicle.
Don‘t have your vehicle towed on the drive wheels
unless you must.
If the vehicle must be towed on the
drive wheels. be sure to follow the speed and distance
restrictions later
in this section or your transmission will
be damaged. If these limitations must be exceeded, then
the drive wheels have
to be supported on a dolly.
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Front Towing
Two- Wheel-Drive Vehicles
Tow Lirnits -- 35 nzph (55 kdh), 50 miles (80 kr.n/h)
If your vehicle is two-wheel drive, use the
following directions:
I. Engage the parking brake.
2. Turn the ignition key to OFF.
3. Clamp the steering wheel in a straight-ahead position
with a clamping device designed for towing service.
(Do not use the vehicle’s steering column lock for this.)
4. Put an automatic or a manual transmission in
NEUTRAL (N).
5. When the vehicle is hooked up, release the
parking brake.
Four-Wheel-Drive Vehicles (Manual Transfer Case)
Tow Lirnits -- 55 rnph (88 knzdh) or legtrl speed limit,
distance
is unlimited
If your vehicle is four-wheel drive with a manual
transfer case, use the following directions:
1. Engage the parking brake.
2. Turn the ignition key to OFF.
3. Clamp the steering wheel in a straight-ahead position
with
a clamping device designed for towing service.
(Do not use the vehicle’s steering column lock for this.)
4. Put an automatic transmission in PARK (P), or a
manual transmission
in FIRST (1).
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