1993 GMC SIERRA engine

antifreeze at the coolant recovery tank. (See “Coolant” in the Index for more
information about the proper coolant mix.)
* Adding only plain water to your cooling system can be dangerous.
Plain water, or some other liquid like alcohol, can boil before the
proper coolant mix will. Your vehicle’s coolant warning system is
for the proper coolant mix. With plain water or the wrong mix, your
engine could get too hot but you wouldn’t get the overheat warning,
Your engine could catch fire and you or others could be burned.
USE
7 50/50 mix of clean water and a proper antifreeze.
I ln cold weather, water can freeze and crack the engine, radiator, heate\
r
:ore and other parts. Use the recommended coolant.
PO206
I * You can be burned if you spill coolant on hot engine parts. CoolQni
A contains ethylene glycol and it will burn if the engine parts are hut
enough. Don’t spill coolant on a hot engine.
When the coolant in the coolant recovery is at
or above COLD, start your
vehicle.
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Prob/ems on the Road
t
e;
K2550
6. Start the engine and let it run until you can feel the upper radiator hose
getting hot. Watch out for the engine fan(s).
7. By this time, the coolant level inside the radiator filler neck m\
ay be
lower.
If the level is lower, add more of the proper mix through the f\
iller
neck until the level reaches the base of the filler neck.
K2515
8. Then replace the pressure cap. Be sure the arrows on the pressure cap
line up like this.
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Engine Fan Noise
This 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 clutch is not engaged. This improves fue\
l economy and
reduces fan noise. Under heavy vehicle loading, trailer towing andlor high
outside temperatures, the fan speed increases when the clutch e\
ngages.
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 disengages.
You may also hear this fan noise when you start the engine. It will go away
as the fan clutch disengages.
If a Tire Goes Fiat
It’s unusual 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.
A rear blowout, particularly on a curve, acts much like a skid and may
require the same correction you’d use in a skid. In any rear blowout, remove
your foot from the accelerator pedal. Get the‘vehicle under control by steering
the way you want the vehicle to go. It may be very bumpy and noisy, but
you can still steer. Gently brake to a stop, well off the road
if possible.
If your tire goes flat, the next part shows how to use your jacking equipment
to change a flat tire safely.
Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage by driv\
ing slowly to a
level place. Turn on your hazard warning flashers.
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If You’re Stuck: In Sand,
Mud,
Ice or Snow
What you don’t want to do when your vehicle is stuck is to spin your
wheels. The method known as “rocking” can help you get o\
ut when you’re
stuck, but you must use caution.
CAUTION - --
I * If you let your tires spin at high speed, they can explode and you or
,A others could be injured. And, the transmission or other parts of the
vehicle can overheat. That could cause an engine compartment fire
or other damage. When you’re stuck, spin the wheels as little as
possible. Don’t spin the wheels above
35 mph (55 krnlh) as shown
I on the speedometer.
;pinning your wheels can destroy parts of your vehicle as well as the
res.
If you spin the wheels too fast while shifting your transmission back
.nd forth, you can destroy your transmission.
NOTICE 1
Rocking your vehicle to get it out:
First, turn your steering wheel left and right. That will clear the area around
your front wheels. Then shift back and forth between
R and a forward gear
(or with a manual transmission, between First or Second gear and Reverse),
spinning the wheels as little as possible. Release the accelerator pedal while
you shift, and press lightly on the accelerator pedal when the transmission is
in gear.
If that doesn’t get you out after a few tries, you may need to be
towed out.
Or, you can use your recovery hooks, if your vehicle has them. If
you do need to be towed out, see “Towing Your Vehicle” in the Index.
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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
Engine Coolant ........................................................................\
........................ 6-42
Power Steering Fluid
........................................................................\
............... 6-46
Windshield Washer Fluid
........................................................................\
......... 6-48
Brake Master Cylinder
........................................................................\
............. 6-49
Replacing Brake System Parts
........................................................................\
.. 6-50
Other Maintenance Items ........................................................................\
........... 6-51
Lubrication
........................................................................\
.................................... 6-52
Electrical System
........................................................................\
......................... 6-54
Battery
........................................................................\
...................................... 6-54
Fuses and Circuit Breakers
........................................................................\
.... 6-64
Bulb Replacement
........................................................................\
.................... 6-54
Exhaust System
........................................................................\
........................... 6-65
Loading Your Vehicle
........................................................................\
.................. 6-67
Tires
........................................................................\
.............................................. 6-72
Inflation-Tire Pressure
........................................................................\
........... 6-73
Tire Inspection and Rotation
........................................................................\
.. 6-78
When It's Time for New Tires
........................................................................\
6-80
Buying New Tires
........................................................................\
.................... 6-81
Wheel Alignment and Tire Balance
............................................................... 6-82
Wheel Replacement
........................................................................\
................. 6-83
Tire Chains
........................................................................\
............................... 6-84
Appearance Care
........................................................................\
........................ 6-84
Cleaning the Inside Of Your Vehicle
............................................................. 6-85
Cleaning the Outside Of Your Vehicle
.......................................................... 6-88
Appearance Care Materials
.r.ikl...rr.r.n.....lr. ........ ... .. 6-91
Vehicle Identification Number
........................................................................\
..... 6-92
Service Parts Identification Label
...................................................................... 6-94
Specification Charts
....++t....,.,.*,..-".,,. .............. , ........... .................... 6-95
Uniform Tire Quality Grading
........................................................................\
.. 6-81
..................................................
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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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