1996 GMC SIERRA manual transmission

Engine Exhaust
I
A CAUTION:
-
Engine exhaust can kill. It contains the gas
carbon monoxide
(CO), which you can’t see or
smell. It can cause unconsciousness and death.
You might have exhaust coming in if:
Your exhaust system sounds strange or different.
Your vehicle gets rusty underneath.
Your vehicle was damaged in a collision.
Your vehicle was damaged when driving over
high points on the road or over road debris.
Repairs weren’t done correctly.
Your vehicle or exhaust system had been
If you ever suspect exhaust is coming into
your vehicle:
Drive it only with all the windows down to
Have your vehicle fixed immediately.
modified improperly.
blow
out any
CO; and
I
Zunning Your Engine While You’re
larked (Automatic Transmission)
It’s better not to park with the engine running. But if you
ever have to, here are some things to know.
Idling the engine with the air system control off
could allow dangerous exhaust into your vehicle
(see the earlier Caution under “Engine Exhaust”).
Also, idling in
a closed-in place can let deadly
carbon monoxide
(CO) into your vehicle even if
the fan switch is at the highest setting. One place
this can happen
is a garage. Exhaust -- with
CO -- can come in easily. NEVER park in a
garage with the engine running.
Another closed-in place can be a blizzard. (See
“Blizzard”
in the Index.)
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/A CAUTION: l!,L- .
Don’t keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches fire.
You or others could be burned.
Check
your oil as soon as possible and have your
vehicle serviced.
I NOTICE:
Damage to your engine from neglected oil
problems can be costly and
is not covered by your
warranty.
Shift Light
SHIFT
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.
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What should I do if my vehicle stalls, or is about
to stall, and
I can’t make it up the hill?
A: If this happens, there are some things you should
do, and these are some things you
must not do.
First, here’s what you shalrlcl do:
Push the brake pedal to stop the vehicle and
keep it from rolling backwards. Also, apply the
parking brake.
If your engine is still running, shift the transmission
to REVERSE
(R), release the parking brake, and
slowly back down the
hill in REVERSE (R).
If your engine has stopped running, you’ll need to
restart
it. With the brake pedal depressed and the
parking brake still applied, shift the transmission to
PARK (P) (or, shift to NEUTRAL (N) if your
vehicle has
a manual transmission) and restart the
engine. Then,
shift to REVERSE (R), release the
parking brake, and slowly back down the
hill as
straight as possible
in REVERSE (R).
As you are backing down the hill, put your left hand
on the steering wheel at the 12 o’clock position. This
way, you’ll be able to tell
if your wheels are straight
and maneuver as you back down.
It’s best that you
back down the
hill with your wheels straight rather
than
in the left or right direction. Turning the wheel
too far to the left or right will increase the possibility
of a rollover.
Here are sonie things you
rnusf not do if you stall, or are
about to stall, when going
up a hill.
Never attempt to prevent a stall by shifting into
NEUTRAL
(N) (or depressing the clutch, if you
have a manual transmission) to “rev-up” the engine
and regain forward momentum. This won’t work.
Your vehicle will roll backwards very quickly and
you could go out
of control.
Instead, apply the regular brake to stop the vehicle. Then
apply the parking brake. Shift to REVERSE
(R), release
the parking brake, and slowly back straight down.
Never attempt to turn around if you are about to stall
when going
up a hill. If the hill is steep enough to
stall your vehicle, it’s steep enough to cause you to
roll over if you turn around. If you can’t make it up
the
hill, you must back straight down the hill.
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&.’ Suppose, after stalling, I try to back down
the hill and decide
I just can’t do it. What
should 1 do?
A: Set the parking brake. put your transmission
in PARK (Pj (or the manual transmission in
FIRST ( I )) and turn off the engine. Leave the
vehicle
and go get some help. Exit on the uphill
side and stay clear
of the path the vehicle would
take if it rolled downhill. Do not shift the transfer
case to
NEUTRAL (N) when you leave the vehicle.
Leave
it in some gear. Shirring the
transter ca-- to NEU 1 dAL (N) can
cause your vehicle to roll even if the transmission
is in PARK (P) (or, if you have the manual
transmission, even if you’re in gear). This
is
because the NEUTRAL (N) position on the
transfer case overrides the transmission. If you
are going to
leave your vehicle, set the parking
brake and shift the transmission to
PARK (P)
(or, put your manual transmission in FIRST (I)).
But do not shift the transfer case to the
NEUTRAL (N) position. Leave the transfer
case in the
2 Wheel, 4 High or 4 I,ow position.
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Driving Downhill
When off-roading takes you downhill, you’ll want to
consider
a number of things:
How steep is the downhill? Will I be able to maintain
vehicle control?
What’s the surface like? Smooth? Rough? Slippery?
Hard-packed dirt? Gravel?
Logs? Boulders?
Are there hidden surface obstacles? Ruts?
What’s at the bottom of the hill‘? Is there a hidden
creek bank or even a river bottom
with large rocks?
If you decide YOU can go down a hill safely, then try to
keep your vehicle headed straight down, and use a low
gear. This way, engine drag can help your brakes and
they won’t have to do all
the work. Descend slowly,
keeping your vehicle under control at all times,
’ A CAUTION:
-
Heavy braking when going down a hill can
cause your brakes to overheat and fade. This
could cause loss
of control and a serious accident.
Apply the brakes lightly when descending
a
hill and use a low gear to keep vehicle speed
under control.
Are there some things
I should not do when
driving down a hill?
At Yes! These are important because if you ignore them
you could lose control and have a serious accident.
0 When driving downhill, avoid turns that take you
across the incline
of the hill. A hill that’s not too
steep to drive down may be too steep to drive across.
You could roll over if you don’t drive straight down.
0 Never go downhill with the transmission in
NEUTRAL (N), or with the clutch pedal depressed
in a manual shift, This is called “free-wheeling.”
Your brakes will have to
do all the work and could
overheat and fade.
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Am I likely to stall when going downhill?
A: It’s much more likely to happen going uphill. But
0
e
a
0
if it happens going downhill, here’s what to do.
Stop your vehicle by applying the regular brakes.
Apply
the parking brake.
Shift
to PARK (P) (or to NEUTRAL (N) with the
manual transmission) and, while still braking, restart
the engine.
Shift back
to a low gear, release the parking brake,
and drive straight down.
If the engine won’t start, get out and get help.
Driving Across an Incline
Sooner or later, an off-road trail will probably go across
the
incline of a hill. If this happens, you have to decide
whether to try
to drive across the incline. Here are some
things
to consider:
0 A hill that can be driven straight up or down may be
too steep
to drive across. When you go straight up or
down a
hill, the length of the wheel base (the
distance from
the front wheels to the rear wheels)
reduces the likelihood the vehicle will tumble end
over end.
But when you drive across an incline, the
much more narrow track width (the distance between
the
left and right wheels) may not prevent the vehicle
from tilting and rolling over. Also, driving across an
incline puts more weight
on the downhill wheels.
This could cause
a downhill slide or a rollover.
0 Surface conditions can be a problem when you drive
across a
hill. Loose gravel, muddy spots, or even wet
grass can cause your tires to slip sideways, downhill.
If the vehicle slips sideways, it can hit something
that will trip it
(a rock, a rut, etc.) and roll over.
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0 Keep your vehicle in good shape. Check all fluid
levels and also the brakes, tires. cooling system and
transmission. These parts can work hard on
mountain roads.
Know how to go down hills. The most important
thing to know is this: let your engine
do some of the
slowing down. Shift
to a lower gear when you go
down a steep or long hill.
If you don’t shift down, your brakes could get
so
hot that they wouldn’t work well. You would then
have poor braking or even none going down a hill.
You could crash. Shift down to let your engine
assist your brakes on
a steep downhill slope.
0
0
0
0
~h CAUTION:
Coasting downhill in NEUTRAL (N) or with the
ignition
off is dangerous. Your brakes will have to
do
all the work of slowing down. They could get so
hot that they wouldn’t work well. You would then
have poor braking
or even none going down a hill.
You could crash. Always have your engine running
and your vehicle in gear when you go downhill.
Know
how to go uphill. You may want to shift down
to a lower gear. The lower gears help cool your engine
and transmission, and
you can climb the hill better.
Stay
in your own lane when driving on two-lane
roads
in hills or mountains. Don’t swing wide or cut
across the center
of the road. Drive at speeds that let
you stay
in your own lane.
As you go over the top of a hill, be alert. There
could be something
in your lane, like a stalled car
or an accident.
You may see highway signs on mountains that warn of
special problems. Examples are long grades, passing or
no-passing zones, a falling rocks area’or winding
roads. Be alert to these and take appropriate action.
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0 If you have an automatic transmission, you can tow
in OVERDRIVE
(@). You may want to shift the
transmission to THIRD (3) or, if necessary, a lower
gear selection if the transmission shifts too often
(eg, 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).
Three important considerations have to do with weight:
the weight
of the trailer,
the weight
of the trailer tongue
and the weight
on your vehicle’s tires.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how
you plan to use your rig. For
example, speed, altitude, road grades, outside
temperature and how much your vehicle is used to pull
a
trailer are all important. And, it can also depend on any
special equipment that you have on your vehicle. Use
one
of the following charts to determine how much
your vehicle can weigh, based upon your vehicle model
and options.
Maximum trailer weight is calculated assuming the
driver and
one passenger are in the tow vehicle and it
has all the required trailering equipment. The weight
of
additional optional equipment, passengers and cargo in
the tow vehicle must be subtracted from the maximum
trailer weight.
Above
the 2,000 lbs. (908 kg) trailer rating, the engine
oil cooler is required
on C/K- 1500 models with gas
engines and
C/K-2500 models with gas engines and
3.73 (or lower) axle ratio.
Above
the 4,000 lbs. (1 800 kg) trailer rating,
heavy-duty or gas shock absorbers are required
on
C- 1500 models, and heavy-duty shock absorbers
or
the off-road chassis package are required on
K-1500 models.
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