1994 GMC SIERRA maintenance

Service
Your GM dealer knows your vehicle best and wants you to be happy with it.
We hope you’ll go to your dealer for all your service needs. You’ll get
genuine
GM parts and GM-trained and supported service people.
We hope
you’ll want to keep your GM vehicle all GM. Genuine GM parts
have one of these marks:
Doing Your Own Service Work
If you want to do some of your own service work, you’ll want to get the
proper
GM Service Manual. It tells you much more about how to service
your vehicle than
this manual can. To order the proper service manual, see
“Service Publications”
in the Index.
You should keep a record with all parts receipts and list the mileage and the
date
of any service work you perform. See “Maintenance Record” in the
Index.
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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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Things that burn can get on hot engine parts and start a fire.
These include liquids like gasoline or diesel fuel, oil, coolant,
brake fluid, windshield washer and other fluids, and plastic or
rubber. You or others could be burned. Be careful not to drop or
I spill things that will burn onto a hot engine.
Before closing the hood, be sure all filler caps are on properly. Pull down
the hood and close it firmly.
Cleaning Your Diesel Engine
NOTICE:
If you spray or pour water or any other liquid on your engine
when it is warm or hot, or when it is running,
you could cause
serious damage to it.
If you ever clean the engine, clean it only
when it is cold.
Noise Control System
The following information relates to compliance with Federal noise
emission standards for vehicles
with a Gross Vehicle Weight Rating
(GVWR) of more than
10,000 pounds (4 536 kilograms). The Maintenance
Schedule booklet provides information on maintaining the noise control
system to minimize degradation
of the noise emission control system during
the life of your vehicle. The noise control system warranty
is given in your
Warranty hooklet.
These standards apply only to vehicles sold
in the United States.
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Tampering With Noise Control System Prohibited
Federal law prohibits the following acts or the causing thereof:
1 . The removal or rendering inoperative by any person, other than for
purposes
of maintenance, repair or replacement, of any device or
element
of design incorporated into any new vehicle for the purpose of
noise control, prior to its sale or delivery to the ultimate purchaser or
while
it is in use; or
2. The use of the vehicle after such device or element of design has been
removed or rendered inoperative by any person.
Among those acts presumed to constitute tampering are the acts listed
below.
Insulation:
Removal of noise shields or underhood insulation.
Engine:
Removal or rendering engine speed governor (if so equipped)
inoperative
so as to allow engine speed to exceed manufacturer
specifications.
Fan and Drive:
Removal of fan clutch (if so equipped) or rendering clutch inoperative.
Removal of fan shroud (if so equipped).
Air Intake:
Removal of air cleaner silencer.
Reversing air cleaner cover.
Exhaust:
Removal of muffler and/or resonator.
Removal of exhaust pipes and exhaust pipe clamps.
Engine Oil (Except Diesel)
It’s a good idea to check your engine oil every time you get fuel. In order to
get an accurate reading, the oil must be warm and the vehicle must be on
level ground.
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Air Cleaner
Refer to the
Maintenance Schedule
to determine when to
replace the air filter.
See “Scheduled
Maintenance Services” in the Index.
NOTICE:
If the air cleaner is off, a backfire can cause a damaging engine
fire. And, dirt can easily get into your engine, which will d\
amage
it. Always have the air cleaner in place when you’re drivin\
g.
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.-. -1 To remove the air
cleaner filter on
a gas
engine or a 6.5 liter
naturally aspirated
diesel,
turn the wing
nuts to the left.
Remove the cover and
change the filter.
Then, unhook the
cover retaining clips
and push the rear
of
the cover toward the
engine.
Automatic Transmission Nuid
When to Check and Change
A good time to check your automatic transmission fluid level is when the
engine oil is changed. Refer
to the Maintenance Schedule to determine
when to change your fluid. See “Scheduled Maintenance Services”
in the
Index.
How to Check
Because this operation can be a little difficult, you may choose to have this
done at
a GM dealership Service Department.
If you do it yourself, be SLIK to follow all the instructions here, or you could
get a false reading on the dipstick.
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How to Add Fluid
Refer to the Maintenance Schedule to determine what kind of transmission
fluid
to use. See “Recommended Fluids and Lubricants” in the Index.
If the fluid level is low, add
only enough of the proper fluid to bring the
level up to the COLD area for a cold check or the HOT area for a hot check.
It doesn’t take much tluid, generally less than a pint. Don’t overfill. We
recommend you use only fluid labeled DEXRON@-111 or DEXRON@-IIE,
because fluids with that label are made especially for your automatic
transmission. Damage caused by fluid other than
DEXRON@-Ill or
DEXRON@-IIE is not covered by your new vehicle warranty.
After adding fluid, recheck the fluid level as described under “How to
Check.”
When the correct fluid level is obtained, push the dipstick back in all
the way; then flip the handle down to lock the dipstick in place.
Manual Fluid
When to Check
A good time to have it checked is when the engine oil is changed. However,
the fluid
in your manual transmission doesn’t require changing.
How to Check
Because this operation can be a little difficult, you may choose to have this
done at a
GM dealership Service Department.
If you do it yourself, be sure to follow all the instructions here, or you could
get
a false reading.
NOTICE:
Too much or too little fluid can damage your transmission. Too
much can mean that some of the fluid could come out and fall on
hot engine parts or exhaust system, starting a fire. Be sure to get
an accurate reading if
you check your transmission fluid.
Check the fluid level only when your engine is off, the vehicle is parked on
a level place and the transmission is cool enough for you to rest your fingers
on the transmission case.
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Then, follow these steps:
I. Remove the filler plug.
2. Check that the lubricant level is up to the bottom of the filler plug hole.
3. If the fluid level is good, install the plug and be sure it is fully seated. If
the fluid level is low, add more fluid as described in the next steps.
How to Add fluid
Here’s how to add fluid. Refer to the Maintenance Schedule to determine
what kind
of fluid to use. See “Recommended Fluids and Lubricants” in the
Index.
I. Remove the filler plug.
2. Add fluid at the filler plug hole. Add only enough fluid to bring the
fluid level up to
the bottom of the filler plug hole.
3. Install the filler plug. Be sure the plug is fully seated.
Hydraulic Clutch
The hydraulic clutch in your vehicle is self-adjusting. A slight amount of
play (1/4 inch to 1/2 inch) in the pedal is normal.
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