1996 GMC SIERRA engine

Turn Signals When Towing a Trailer
The green 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 green 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 be~m 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 should use
THIRD
(3) (or, as you need to, a lower gear) when
towing a trailer. Operating your vehicle in THIRD
(3)
when towing a trailer will minimize heat build-up and
extend
the life of your transmission
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.
2.
3.
4.
5.
6.
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.
If you have a four-wheel-drive vehicle, be sure
the transfer case
is in a drive gear and not in
NEUTRAL
(N).
Release the regular brakes. 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
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while
you:
0 Start your engine;
Shift into a gear; and
0 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.
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.
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2. Get the vehicles close enough so the jumper cables
can reach, but be sure the ve.hicles 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,
if you have this
option. 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!
NOTICE:
I
~~~ ~
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 011
each battery.
A CAUTION:
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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A CAUTION:
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.
5. 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
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.
1 things you should know. Positive (+) will go to
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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8. 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.
9.
10.
11.
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.
Now start the vehicle with the good battery and run
the engine
for awhile.
Try to start the vehicle with the dead battery.
If it won’t start after a few tries, it probably
needs service.
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12. Remove the cables in reverse order to prevent
electrical shorting. Take care that they don’t touch
each other or any other metal.
I
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:
That your vehicle .has rear-wheel drive, or that it has
The make, model and year of your vehicle.
Whether you can move the shift lever for the
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.
the four-wheel-drive
option.
transmission
and transfer case, if you have one.
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Engine Overheating
(Gasoline Engine)
You will find a coolant temperature gage on your
vehicle’s instrument panel.
If your vehicle has a
diesel engine, see “Engine Overheating” in the Diesel
Engine Supplement.
If Steam Is Coming From Your Engine
A CAUTION:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see
or hear steam coming
from it. Just turn it
off and get everyone away
from the vehicle until it cools down. Wait until
there is no sign
of steam or coolant before
opening the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch
fire. You
or others could be badly burned. Stop your engine
if it overheats, and get out of the vehicle until the
engine is cool.
NOTICE:
If your engine catches fire because you keep
driving with no coolant, your vehicle can be
badly damaged. The costly repairs would not be
covered by your warranty.
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