1994 GMC SIERRA specifications

Checking Things Under the Hood (continued)
Windshield Washer Fluid
................................. 6-45
Brake Master Cylinder
................................... 6-46
Replacing Brake System Parts
................................ 6-49
Other Maintenance Items
.................................... 6-49
Windshield Wiper Blade Inserts
.............................. 6-50
FluidLeakCheck
.......................................... 6-51
Lubrication
............................................... 6-51
Battery .................................................. 6-52
Vehiclestorage
......................................... 6-52
Bulb Replacement
......................................... 6-53
Fuses and Circuit Breakers
.................................. 6-62
Exhaustsystem
........................................... 6-64
Loading Your Vehicle
...................................... 6-64
Tires .................................................... 6-71
Inflation-Tire Pressure
.................................. 6-71
Tire Inspection and Rotation
............................... 6-73
When it’s Time for New Tires
............................. 6-74
Buying New Tires
....................................... 6-76
Uniform Tire Quality Grading
............................. 6-77
Wheel Alignment and Tire Balance
......................... 6-78
Wheel Replacement
..................................... 6-78
Tire Chains
............................................ 6-79
Appearancecare
.......................................... 6-80
Cleaning the Inside of Your Vehicle
......................... 6-81
Cleaning the Outside
of Your Vehicle ....................... 6-84
Appearance Care Materials
.................................. 6-87
Vehicle Identification Number
................................ 6-88
Service Parts Identification
Label ............................. 6-90
Specifications Charts
..................................... 6-91
6-2
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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.
6-4
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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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I
I
I
To Check Engine Oil
Turn off the engine
and give the oil a few
minutes to drain back
into the
oil pan. If you
don’t, the oil dipstick
might
not show the
actual level.
Pull out the dipstick and clean it with
a paper towel or cloth, then push it
back in all the way. Remove it again, keeping the tip lower.
When to Add Oil
If the oil is at or below the ADD mark, then you’ll need to add some oil. But
you must use the right kind. This section explains what kind of oil
to use.
For crankcase capacity, see “Capacities and Specifications”
in the Index.
NOTICE:
Don’t add too much oil. If your engine has so much oil that the
oil level gets above the upper mark that shows the proper
operating range, your engine could be damaged.
6-18
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To Check Engine Oil
Pull out the dipstick and clean it with a paper towel or a cloth, then push it
back in all the way. Remove it again, keeping the tip lower.
When to Add Oil
If the oil is at or below the ADD line, then you’ll need to add some oil. But
you must use the right kind. This section explains what kind
of oil to use.
For crankcase capacity, see “Capacities and Specifications” in
the Index.
NOTICE:
Don’t add too much oil. If your engine has so much oil that the
oil level gets above the proper operating range, your engine
could be damaged.
6-25
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Engine Identification
The eighth character in your VIN is the engine code. This code will help
'ou identify your engine, specifications, and replacement parts.
4- '
4
Y
1
P
6-89
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10.
11.
12.
13.
14.
15.
16.
17.
SPARK PLUG REPLACEMENT* - Replace spark plugs with the
type listed in Section
6. See “Specification Charts” in the Index.
SPARK PLUG WIRE INSPECTION - Clean wires and inspect for
bums, cracks or other damage. Check the wire boot
fit at the distributor
and at the spark plugs. Replace wires
as needed.
-f‘A fluid loss in these systems may indicate a problem. Have them
inspected and repaired at once.
EGR SYSTEM INSPECTION* - Conduct EGR SYSTEM CHECK
as described in the Service Manual.
ELECTRONIC VACUUM REGULATOR VALVE (EVRV)
INSPECTION*
- Inspect filter for excessive contamination or
plugging. If required, clean element with
a solution of biodegradable
soap and water, let dry and reinstall element.
ENGINE TIMING CHECK AND DISTRIBUTOR CHECK
(SOME MODELS)*$
- Adjust timing to underhood label
specifications. Inspect the inside and outside of the distributor cap
and
rotor for cracks, carbon tracking and corrosion. Clean or replace as
needed.
FUEL TANK, CAP AND LINES INSPECTION*$ - Inspect the
fuel tank, cap and lines for damage or leaks. Remove
fuel cap, inspect
gasket for an even filler neck imprint, and any damage. Replace parts
as needed.
THERMOSTATICALLY CONTROLLED AIR CLEANER
INSPECTION*A
- (If so equipped.) Inspect all hoses and ducts for
proper hook-up. Be sure
the valve works properly.
SINGLE ENGINE ACCESSORY DRIVE (SERPENTINE) BELT
INSPECTION*
- Inspect belt. Look for cracks, fraying, wear, and
proper tension. Adjust or replace
as needed.
* An Emission Control Service
ANoise Emission Control Service
$The California Air Resources Board has determined that the failure to
perform this maintenance item will not nullify the emission warranty
or
limit recall liability prior to the completion of the vehicle useful life.
General Motors, however, urges that all recommended maintenance
services be performed at
the indicated intervals and the maintenance be
recorded.
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24. DRIVE AXLE SERVICE? - Check readfront axle fluid level and
add
as needed. Check constant velocity joints and axle seals for
leaking.
0
0
0
0
Locking differential - Drain fluid at first oil change and refill.
Check fluid level and add
as needed at subsequent oil changes. In
dusty areas, or trailer towing applications drain fluid at every
15,000 miles (24 135 kilometers) and refill.
Standard differential - Check fluid level and add as needed at
every
oil change. In dusty areas, or trailer towing applications,
drain fluid every
15,000 miles (24 I35 kilometers) and refill.
More frequent lubrication may be required on heavy-duty or
off-road use.
3500 HD Models - 3500 HD Models with applications requiring
extreme overload/trdiler tow conditions
and high speed conditions
(above 45 mph (72
kdh)) for extended periods of time must
change drive axle fluid every
3,000 miles (4828 kilometers) or 3
months, whichever comes first, OR must use 75W-140 synthetic
fluid meeting
GM specifications. See “Recommended Fluids and
Lubricants” at the end of this section for the proper fluid to use.
25.
BRAKE SYSTEM INSPECTION-f - When the engine oil is
changed, inspect the lines and hoses for proper hookup, binding, leaks,
cracks, chafing, etc. Check the parking brake adjust, and the fluid level
in the master cylinder. A low fluid level can indicate worn disc brake
pads which may need
to be serviced.
When the wheels are removed for rotation, inspect disc brake pads for
wear and rotors for surfxe condition. Also inspect drum brake linings
for wear and cracks. Inspect other brake parts, including drums, wheel
cylinders, parking brake, etc., at the same time. Remove any
rust or dirt
from the wheel and mounting surfaces before mounting the wheel.
Inspect brakes more often if driving habits or conditions result in
frequent braking.
?A fluid loss in these systems may indicate a problem. Have them
inspected and repaired at once.
7-22
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