1994 GMC SIERRA fuel

Driving Guidelines
Off-Road Driving with Your Four-wheel Drive Vehicle
This off-road guide is for vehicles that have four-wheel drive.
Also, see “Anti-lock Brakes”
in the Index.
If your vehicle doesn’t have four-wheel drive, you shouldn’t drive off-road
unless you’re on
a level, solid surface.
Off-road driving can be great
fun. But it does have some definite hazards.
The greatest of these is the terrain itself.
“Off-roading” means you’ve left the great North American road system
behind. Traffic lanes aren’t marked. Curves aren’t banked. There are
no
road signs. Surfaces can be slippery, rough, uphill or downhill. In short,
you’ve gone right back to nature.
Off-road driving involves some new skills. And that’s
why it’s very
important that you read this guide. You’ll find many driving tips and
suggestions. These will help make your off-road driving safer and more
enjoyable.
Before You Go Off-Roading
There are some things to do before you go out. For example, be sure to have
all necessary maintenance and service work done. Be sure you read
all the
information about your four-wheel drive vehicle
in this manual. Is there
enough fuel? Is the spare tire
fully inflated? Are the fluid levels up where
they should be? What are the local laws that apply
to off-roading where
you’ll
be driving’? If you don’t know, you should check with law
enforcement people
in the area. Will you be on someone’s private land‘? If
so, be sure to get the necessary permission.
Loading Your Vehicle for Off-Road Driving
There are some important things to remember about how to load your
vehicle.
0 The heaviest things should be on the load floor and forward of your
rear axle. Put heavier items as far forward as you can.
Be sure the load is secured properly, so driving on the off-road terrain
doesn’t toss things around.
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After Off-Road Driving
Remove any brush or debris that has collected on the underbody, chassis or
under the hood. These accumulations can be
a fire hazard.
After operation
in mud or sand, have the brake linings cleaned and checked.
These substances can cause glazing and uneven braking. Check the body
structure, steering, suspension, wheels, tires, and exhaust system for
damage. Also, check the fuel lines and cooling system for any leakage.
Your vehicle will require more frequent service due to off-road use. Refer
to the Maintenance Schedule for additional information.
Driving at Night
Night driving is more dangerous than day driving. One reason is that some
drivers are likely to be impaired
- by alcohol or drugs. with night vision
problems,
or by fatigue.
Here are some tips
on night driving.
Drive defensively.
Don’t drink and drive.
a Adjust your inside rearview mirror to reduce the glare from headlights
behind you.
Since you can’t see as well, you may need to slow down and keep more
space between you and other vehicles.
Slow down, especially on higher speed roads. Your headlights can light
up only so much road ahead.
In remote areas, watch for animals.
If you’re tired, pull off the road in a safe place and rest.
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Reduce your speed according to your speedometer, not to your sense of
motion. After driving for any distance at higher speeds, you may tend
to
think you are going slower than you actually are.
Before Leaving on a Long Trip
Make sure you’re ready. Try to be well rested. If you must start when you’re
not fresh
- such as after a day’s work - don’t plan to make too many
miles that first part
of the journey. Wear comfortable clothing and shoes you
can easily drive in.
Is your vehicle ready for a long trip? If you keep it serviced and maintained,
it’s ready to go.
If it needs service, have it done before starting out. Of
course, you’ll find experienced and able service experts
in Vehicle
dealerships all across
North America. They’ll be ready and willing to help if
you need it.
Here are some things you can check before a trip:
Windshield Washer Fluid: Is the reservoir full? Are all windows clean
inside and outside?
Wiper Blades: Are they in good shape‘?
Fuel, Engine Oil, Other Fluids: Have you checked all levels?
0 Lights: Are they all working? Are the lenses clean‘?
0 Tires: They are vitally important to a safe, trouble-free trip. Is the tread
good enough for long-distance driving‘? Are the tires all inflated
to the
recommended pressure‘?
0 Weather Forecasts: What’s the weather outlook along your route?
Should you delay your trip
a short time to avoid a major storm system?
0 Maps: Do you have up-to-date maps?
Highway Hypnosis
Is there actually such a condition as “highway hypnosis”? Or is it just plain
falling asleep at the wheel?
Call it highway hypnosis, lack of awareness, or
whatever.
There is something about
an easy stretch of road with the same scenery,
along with the hum of the tires on
the road, the drone of the engine, and the
rush of the wind against the vehicle that can make you sleepy. Don’t let it
happen to you! If
it does, your vehicle can leave the road in less than a
second, and you could crash and be injured.
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I
Run your engine only as long as you must. This saves fuel. When you run
the engine, make it go a little faster than just idle. That is, push the
accelerator slightly. This uses less fuel for the heat that you get and it keeps
the battery (or batteries) charged.
You will need a well-charged battery (or
batteries) to restart the vehicle, and possibly for signaling later on with your
headlights. Let the heater run for awhile.
If you have a diesel engine, you may have to run it at a higher speed to get
enough heat. Then, shut the engine off and close
the window almost all the
way to preserve the heat. Start the engine again and repeat this only when
you feel really uncomfortable from the cold. But do it as little as possible.
Preserve the fuel
as long as you can. To help keep warm, you can get out of
the vehicle and do some fairly vigorous exercises every half hour or so until
help comes.
Power Winches
If you wish to use a power winch on your vehicle, only use it when your
vehicle
is stationary or anchored.
When operating a power winch on your vehicle, always leave the\

transmission
in "N" (Neutral). Leaving a automatic transmission
in "P" (Park) while using a power winch may damage the
transmission.
Also, leaving an automatic or manual transmission
in gear while using a power winch may damage the
transmission.
Use the regular brakes, set the parking brake, or block the wheels to keep
your vehicle
from rolling.
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Every vehicle is ready for some trailer towing. If it was built with trailering
options,
as many are, it’s ready for heavier trailers. But trailering is different
than just driving your vehicle by itself. Trailering means changes
in
handling, durability, and fuel economy. Successful, safe trailering takes
correct equipment, and
it has to be used properly.
That’s the reason for this section. In it are many time-tested, important
trailering tips and safety rules. Many
of these are important for your safety
and that of your passengers.
So please read this section carefully before you
pull
a trailer.
If You Do Decide To Pull A Trailer
If you do, here are some important points.
There are many different laws having to do with trailering. Make sure
your rig will be legal,
not only where you live but also where you’ll be
driving. A good source for this information can be state or provincial
police.
Consider using a sway control if your trailer will weigh 4,000 pounds
(1 800 kg) or less. You should always use a sway control if your trailer
will weigh more than 4,000 pounds (I 800 kg).
You can
ask a hitch dealer about sway controls.
0 Don’t tow a trailer at all during the first 500 miles (800 km) your new
vehicle is driven. Your engine, axle or other parts could be damaged.
Then, during the first 500 miles (800 km) that you tow a trailer, don’t
drive over
50 mph (80 kdh) and don’t make starts at full throttle. This
helps your engine and other parts
of your vehicle wear in at the heavier
loads.
Three important considerations have
to do with weight:
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.
You can ask your dealer for our trailering information or advice,
or you can
write us at
the address listed in your Warranty and Owner Assistance
Information Booklet.
In Canada, write to General Motors
of Canada Limited, Customer
Assistance Center,
1908 Colonel Sam Drive, Oshawa, Ontario LlH 8P7.
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Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When the clutch is engaged,
the fan spins faster
to provide more air to cool the engine. In most every day
driving conditions
the fan is spinning slower and clutch is not fully engaged.
This improves fuel economy and reduces fan noise. Under heavy vehicle
loading, trailer towing and/or high outside temperatures, the fan speed
increases as
the clutch more fully engages. So you may hear an increase in
fan noise. This is normal and should not be mistaken as the transmission
slipping or making extra shifts. It is merely the cooling system functioning
properly. The fan will slow down when additional cooling is not required
and
the clutch partially disengages.
You may also hear
this fan noise when you start the engine. It will go away
as
the fan clutch partially disengages.
If a Tire Goes Flat
It’s UfluSual for a tire to “blow out” while you’re driving, especially if you
maintain your tires properly. If air goes out of a tire, it’s much more likely to
leak
out slowly. But if you should ever have a “blowout,’’ here are a few tips
about what
to expect and what to do:
If a front tire fails, the flat tire will create a drag that pulls the vehicle
toward that side. Take your foot off
the accelerator pedal and grip the
steering wheel firmly. Steer to maintain lane position, then gently brake to a
stop well
out of the traffic lane.
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Service & Appearance Care
Section
Here you will find information about the care of your vehicle . This section
begins with service and fuel information. and then it shows how to check
important fluid and lubricant levels
. There is also technical information
about your vehicle. and a section devoted to its appearance care
.
Service ................................................... 6-3
Fuel (Gasoline Engines)
...................................... 6-4
Diesel Fuel Requirements and Fuel System
...................... 6-5
Checking Things Under the Hood
............................. 6-15
HoodRelease
.......................................... 6-15
Cleaning Your Diesel Engine
.............................. 6-16
Noise Control System .................................... 6-16
Engine Oil (Except Diesel)
................................ 6-17
Engine Oil (Diesel Engines)
............................... 6-24
iri
Air Cleaner ............................................ 6-29
Automatic Fluid ........................................ 6-30
ManualFluid
........................................... 6-33
Hydraulic Clutch
........................................ 6-34
RearAxle ............................................. 6-35
mnsfer Case
.......................................... 6-36
FrontAxle
............................................. 6-37
Engine Coolant
......................................... 6-38
Power Steering Fluid
.................................... 6-43
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NOTICE:
If you try to do your own service work without knowing enough
about it, your vehicle could be damaged.
__ .
Maintenance Schedule
Section 7 of this manual, “Scheduled Maintenance Services”, explains the
maintenance your new vehicle needs, and when
it should be done. It also
has a form that you can use to record the maintenance work done on your
vehicle. Be sure
to read this information.
Fuel (Gasoline Engine)
If your vehicle has a diesel engine, see “Diesel Fuel Requirements and Fuel
System” in this Section. For vehicles with gasoline engines, please read this.
Use regular unleaded gasoline rated at
87 octane or higher. It should meet
specifications
ASTM D48 14 in the U.S. and CGSB 3.5-92 in Canada.
These fuels should have the proper additives, so you should not have to add
anything to the
fuel.
In the U.S. and Canada, it’s easy to be sure you get the right kind of
gasoline (unleaded). You’ll see “UNLEADED” right on the pump. And only
unleaded nozzles will fit into your vehicle’s filler neck.
Be sure
the posted octane is at least 87. If the octane is less than 87, you
may get a heavy knocking noise when
you drive. If it’s bad enough, it can
damage your engine.
If you’re using fuel rated at 87 octane or higher and you still hear heavy
knocking, your engine needs service. But don’t worry if
you hear a little
pinging noise
when you’re accelerating or driving up a hill. That’s normal
and
you don’t have to buy a higher octane fuel to get rid of pinging. It’s the
heavy, constant knock that means you have
a problem.
What about gasoline with blending materials that contain oxygen
(oxygenates), such as
MTBE or alcohol?
MTBE is “methyl tertiary-butyl ether.’’ Fuel that is no more than 15%
MTBE is fine for your vehicle.
Ethanol is ethyl or grain alcohol. Properly-blended fuel that is no more than
10% ethanol is fine for your vehicle.
Methanol is methyl or wood alcohol.
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