1993 GMC SIERRA fuel

may not realize the surface is slippery until your vehicle is skidding. Learn to
recognize warning clues-such as enough water, ice
or packed snow on the
road to make a “mirrored surface’’-and slow down when you have \
any
doubt.
Remember: the rear wheel anti-lock braking system (RWAL) helps\
avoid only
a rear braking skid. In a braking skid (where the front wheels are no longer
rolling), release enough pressure on the brakes to get the front wheels rolling
again. This restores steering control. Push the brake pedal dow\
n steadily
when you have to stop suddenly.
As long as the front wheels are rolling, you
will have steering control. Steer the way you want to go.
Off-Road Driving with Your FourcWheel
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, so\
lid surface.
Off-road driving can be great fun. But it does have some defi\
nite 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 a\
re 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-roa\
ding 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.
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Your Driving and the Road
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 th\
e body
structure, steering, suspension, wheels, tires, and exhaust syste\
m 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
Section
7 for additional information.
Driving at Night
I
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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. Remember, this is the most dangerous time.
Don’t drink and drive (See “Drunken Driving” in the Index for more on
this problem).
Adjust your inside rear view mirror to reduce the glare from headlights
Since you can’t see as well, you may need to slow down and keep
behind
you.
more space between you and other vehicles. It’s hard
to tell how fast
the vehicle ahead is going just
by looking at its taillights.
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close behind you, you can allow a little extra time and flash\
your brake lights (in addition to your turn signal) as extra warning that you are about to slow
down and exit.
The exit ramp can be curvea, somerlmes quite sharply. The exit\
speed is
usually posted. 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.\
For example,
40 rnph (65 km/h) might seem like only 20 mph (30 km/h). Obviously, this
could lead to serious trouble
on a ramp designed for 20 mph (30 kmlh)!
Driving a Long Distance
Although most long trips today are made on freeways, there are\
still many
made on regular highways.
Long-distance driving on freeways and regular highways is the s\
ame in some
ways. The trip has to be planned and the vehicle prepared, you drive at\

higher-than-city speeds, and there are longer turns behind the \
wheel. You’ll
enjoy your trip more
if you and your vehicle are in good shape. Here are
some tips for a successful long trip.
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 \
your vehicle’s
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
Wiper Blades: Are they in good shape?
Fuel, Engine Oil, Other Fluids: Have you checked all levels?
Lights: Are they all working? Are the lenses clean?
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? inside and outside?
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AM480043
Run your engine only as long as you musk. 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 yo\
u 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 lget 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.
If You're Stuck in Deep Snow
This manual explains how to get the vehicle out of deep snow without
damaging it. See "Rocking Your Vehicle" in the Index.
Towing a mailer
CAUTION I
If you don't use the correct equipment and drive properly, you ca\
n
lose control when you pull a trailer. For example, if the trailer is too
heavy, the brakes may not work well-or even at all. You and your
passengers could be seriously injured. Pull a trailer only if \
you have
followed all the steps in this section.
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z
Your Driving and the Road
NOTICF
Pulling a trailer improperly can damage your vehicle and result in costly
repairs
not covered by your warranty. To pull a trailer correctly, follow the
advice in this section.
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 chan\
ges isn 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. .
0 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 (1800 kg). You can ask a hitch
dealer about sway controls.
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 km/ti) and don’t make ,starts at full throttle. T\
hat
will help your engine and other parts of your vehicle wear in at the
heavier load$.
Three important considerations have to do with weight:
Weight
Weight of the Trailer
How heavy can a trailer safely be?
It should never be more than 13,500 Ibs. (6125.6 kg). But even \
that can be
too heavy. It depends on how you plan to use your rig. For example, speed,
altitude, ‘road grades, outside temperature, and how much your vehicle is
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Service & Appearance Care
.....
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
...................................................... 6-6
Checking Things Under the Hood
..................................................................... 6-17
Hood Release
........................................................................\
.......................... 6-18
Cleaning Your Diesel Engine
........................................................................\
.. 6-19
Noise Control System
........................................................................\
............. 6-19
Engine Oil (Except Diesel)
........................................................................\
..... 6.20
Engine Oil (Diesel Engines)
........................................................................\
... 6-26
Air Cleaner
........................................................................\
............................... 6-31
Automatic Transmission Fluid
........................................................................\
. 6-33
Manual Transmission Fluid
........................................................................\
..... 6-36
Hydraulic Clutch
........................................................................\
....................... 6-37
Transfer Case
........................................................................\
.......................... 6-39
Front Axle ........................................................................\
................................. 6-40
Rear Axle
........................................................................\
................................. 6-41
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Service & Appearance Care
1 If you try to do your own service work without knowing enough ab\
out it, I
1 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.
-I .. >. ’ , .
Fuel (Gasoline Engines)
If your vehicle has a diesel engine, see “Diesel Fuel Requi\
rements 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 D4814 in the
U.S. and CGSB 3.592 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.
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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,\
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.
le1 that is more than
5% methanol is bad for your vehicle. Don’t use it.
can corrode metal parts in your fuel system and also damage plastic
and rubber parts. That damage wouldn’t be covered under your warranty
And even at
5% or less, there must be “cosolvents” and corrosion
- ~wenters in this fuel to help avoid these problems.
Gasolines for CIeaner Air
Your use of gasoline with detergent additives will help prevent depo\
sits from
forming in your engine and fuel system. That helps keep your engine in tune
and your emission control system working properly. It’s good \
for your vehicle,
and you’ll be doing your part for cleaner air.
Many gasolines are now blended with materials that called
oxygenates.General Motors recommends that you use gasolines with \
these
blending materials, such as MTBE and ethanol. By doing
so, you can help
clean the air, especially in those parts
of the country that have higher carbon
monoxide levels.
In addition, some gasoline suppliers are now producing reformulated \
gasolines. These gasolines are specially designed to reduce vehicle
emissions. General Motors recommends that you use reformulated g\
asoline.
By doing
so, you can help clean the air, especially in those parts of the
country that have high ozone levels.
You should ask your service station operators
if their gasolines contain
detergents and oxygenates, and
if they have been reformulated to reduce
vehicle emissions.
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