1997 GMC SIERRA engine

Turn Signals When Towing a Trailer
The arrows on your instrument panel will flash
whenever you signal a turn or lane change. Properly
hooked up, the trailer lamps will also flash, telling other
drivers you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will flash for turns even if the bulbs
on the trailer
are burned out. Thus, you may think drivers behind you
are seeing your signal when they are not. It’s important
to check occasionally to be sure the trailer bulbs are
still working.
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 km/h) to reduce the
possibility of engine and transmission overheating. If you have an automatic transmission, you can tow
in
AUTOMATIC OVERDRIVE (a). 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.
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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. Apply your regular brakes, but don't shift into
PARK
(P) yet for an automatic transmission, or into
gear for a manual transmission.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb
the load.
4. 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.
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.
c
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).
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When You Are Ready to Leave After
Parkine
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.
Trailer Wiring Harness
A seven-wire harness is stored under the rear end of
your vehicle, between
the frame rails. An electrical
connector will need to be installed at the trailer end of
the harness, by a qualified electrical technician. For
additional trailer wiring and towing information please
consult your
GM dealer. Securely attach the harness to
the trailer, then tape or strap
it to your vehicle’s frame
rail. Be sure you leave it loose enough
so the wiring
won’t bind or break when turning with the trailer, but
not
so loose that it drags on the ground. Store the
harness in its original position. Wrap the harness
together and tie
it neatly so it won’t be damaged. If you
tow
a trailer, your Center High-Mounted Stoplamp
(CHMSL) may not be properly visible from behind.
You
should select a trailer with a CHMSL on it or, if one is
not available, have one installed. See your
GM dealer
about how to connect your vehicle’s wiring
to a
trailer CHMSL.
Check periodically to see that all hitch nuts and bolts
are tight.
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Using a Transfer Case Mounted Power
Take-Off (Automatic Transmission)
1. Set the parking brake.
2. Turn the ignition off.
3. Shift the transfer case into NEUTRAL (N).
4. Shift the transmission into NEUTRAL (N).
5. Engage the PTO.
If you are going to drive the vehicle, shift the
transfer case into the range you want. Turn the
ignition to START. Then apply the regular brakes
and release the parking brake.
6. Shift the transmission to THIRD (3) to start the PTO.
7. Release the regular brakes to drive the vehicle.
Disengaging a Power Take-OFF
1. Turn the ignition off.
2. Put the transmission in PARK (P).
3. Release the PTO
4. Restart the engine.
Step-Bumper Pad
If your vehicle has a rear step bumper, it may be equipped
with a rear step pad at the center of the bumper.
If you will be using the
bumper to tow a trailer, you
must remove the center
cutout circle to install
the trailer ball. You must
also remove both outer
cutouts to attach the trailer
safety chains.
To remove the pad, lift the
edge
of the pad from the
rear of the bumper and
the pad releases from the
bumper holes, lift the
pad
off.
swing it forward. When
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Section 5 Problems on the Road
Here you’ll find what to do about some problems that can occur on the road.
5-2
5-3
5-3
5-8
5-1 1
Hazard Warning Flashers
Other Warning Devices
Jump Starting
Towing Your Vehicle
Engine Overheating (Gasoline Engine) Cooling
System
-- Gasoline Engines
Engine Fan Noise
If a Tire
Goes Flat
Changing
a Flat Tire
If You’re Stuck: In Sand,
Mud, Ice or Snow
5- 13
5-2 1
5-2 1
5-22
5-34
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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
fmly on both vehicles involved in the
jump stat 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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Using a match near a battery can cause battery
gas to explode. People have been hurt doing this,
and some have been blinded. Use a flashlight if
you need more light.
Be sure the batteries have enough water. You
don’t need to add water to the Delco Freedom@
battery (or batteries) installed in every new
GM
vehicle. But if a battery has filler caps, be sure
the right amount of fluid is there.
If it is low, add
water to take care
of that first. If you don’t,
explosive gas could be present.
Battery fluid contains acid that can burn you.
Don’t get it on you.
If you accidentally get it in
your eyes
or on your skin, flush the place with
water and get medical help immediately.
Check that the jumper cables don’t have loose or
missing insulation.
If they do, you could get a shock.
The vehicles could be damaged too.
Before you connect the cables, here are some basic
things you should know. Positive
(+) will go to
positive
(+) and negative (-) will go to negative (-)
or a metal engine part. Don’t connect positive (+) to
negative
(-) or you’ll get a short that would damage
the battery and maybe other
parts too.
Fans or other moving engine parts can injure you
badly. Keep your hands away from moving parts
once the engines are running.
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7. Now connect the black
negative
(-) cable to
the good battery’s
negative
(-) cable.
Don’t let the other end touch anything
until the next
step. The other end of the negative
(-) cable doesn’t go
to the dead battery. It goes to a heavy unpainted metal
part of the vehicle with the dead battery. 8. Attach the cable at least 18 inches (45 cm) away
from the dead battery, but not near engine parts that
move. The electrical connection is just as good there,
but the chance
of sparks getting back to the battery is
much less.
9. Now start the vehicle with the good battery and run
the engine for awhile.
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