1994 GMC SIERRA service

Explanation Of Scheduled Mainienance Services
Below are explanations of the services listed in the maintenance charts.
The proper fluids and lubricants to use are listed in this section. Make sure
whoever services your vehicle uses these. All parts should be replaced and
all necessary repairs done before you or anyone else drives the vehicle.
1. ENGINE OIL AND OIL FILTER CHANGE“‘ - ALWAYS USE
SJ3 ENERGY CONSERVING I1 (GASOLINE ENGINE) OR CF-4/SH
(DIESEL ENGINE) QUALITY OILS
OF THE PROPER VISCOSITY.
To determine the preferred viscosity oil for your vehicle’s engine (e.g.
SAE 5W-30 or 10W-30), see “Engine Oil”
in the Index.
2. CHASSIS LUBRICATION - Lubricate the front suspension, king
pin bushings, steering linkage, transmission, and transfer case shift
linkage, parking brake cable guides, rear driveline center splines and
front axle propshaft splines, brake pedal springs, and clutch pedal
springs at the intervals specified.
If you have a 3500
HD, lubricate the king pins and king pin bushings,
every
1,500 miles (2500 km) for Maintenance Schedule I, or every
3,000 (5000 km) for Maintenance Schedule 11.
Ball joints and king pin bushings should not be lubricated unless their
temperature
is 10” F (-12”C), or higher. When the weather is cold, let
them warm up before lubrication or
they could be damaged.
Also, be sure
to check all the vehicle fluid levels at this time.
3.
CLUTCH FORK BALL STUD LUBRICATION (5-SPEED
MANUAL TRANSMISSION WITH DEEP LOW
) - Lubricate the
clutch fork ball stud through the fitting
on the clutch housing.
Lubricant must be added “sparingly” to
the fitting, as only .0066 lb.
(.003 kg) is required to lubricate the ball stud surface. Do not add
lubricant more often than the intervals
in the Maintenance Charts. Too
much lubricant will damage the clutch assembly.
4. COOLING SYSTEM SERVICE”’? - Drain, flush and refill system
with new coolant. See “Engine Coolant” in the Index for
the proper
coolant and mixture to use
in your vehicle.
Also inspect the hoses and replace them
if they are cracked, swollen, or
deteriorated. Tighten all hose clamps (except constant tension clamps).
Remove debris and clean the outside of the radiator and air
conditioning condenser. Wash the radiator neck.
To ensure proper
operation, pressure test.
the radiator and cap.
* An Emission Control Service
?A fluid
loss in these systems may indicate a problem. Have them
inspected and repaired at once.
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5. AIR CLEANER FILTER REPLACEMENT* - Replace at every
30,000 miles (50 000 km) or more often under dusty conditions. Ask
your dealer for the proper replacement intervals for your driving
conditions.
6. FRONT WHEEL BEARING REPACK (2-WHEEL DRIVE
ONLY)
- Clean and repack the front wheel bearings at each brake
relining, or at
the specified interval, whichever comes first.
7. TRANSMISSION SERVICE’/-
Automatic Transmission
- Change the transmission fluid and filter
every
15,000 miles (25 000 km) for vehicles under 8,600 GVWR or
every 12,000 miles
(20 000 km) for vehicles over 8,600 GVWR if the
vehicle is mainly driven under one or more
of these conditions:
In heavy city traffic.
0 Where the outside temperature regularly reaches 90°F (32°C) or
0 In hilly or mountainous terrain.
higher.
Frequent
trailer pulling.
Uses such as taxi, police, delivery or other commercial service.
If the vehicle
is not used mainly under any of these conditions, change
the fluid and filter every
30,000 miles (50 000 km) for vehicles under
8,600
GVWR or every 24,000 miles (40 000 km) for vehicles over
8,600 GVWR see “Automatic Transmission Fluid”
in the Index for
more information.
Manual Transmission - Transmission fluid does not require periodic
changing.
8. CDRV SYSTEM INSPECTION* - Check the Crankcase
Depression Regulator Valve System for any worn, plugged or collapsed
hoses. Have the system checked as described in the Service Manual.
9. FUEL FILTER REPLACEMENT*$ - Replace the fuel filter at the
specified interval or sooner if clogged.
?A fluid loss
in these systems may indicate a problem. Have them
inspected and repaired at once.
:i: An Emission Control Service
$The California Air Resources Board bas determined that the failure to
perform this maintenance item will not
nullify the emission warranty or
limit recall liability prior to the completion
of the vehicle useful life.
General Motors, however, urges that all recommended maintenance
services be performed at the indicated intervals and the maintenance be
recorded.
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10.
11.
12.
13.
14.
15.
16.
17.
SPARK PLUG REPLACEMENT* - Replace spark plugs with the
type listed in Section
6. See “Specification Charts” in the Index.
SPARK PLUG WIRE INSPECTION - Clean wires and inspect for
bums, cracks or other damage. Check the wire boot
fit at the distributor
and at the spark plugs. Replace wires
as needed.
-f‘A fluid loss in these systems may indicate a problem. Have them
inspected and repaired at once.
EGR SYSTEM INSPECTION* - Conduct EGR SYSTEM CHECK
as described in the Service Manual.
ELECTRONIC VACUUM REGULATOR VALVE (EVRV)
INSPECTION*
- Inspect filter for excessive contamination or
plugging. If required, clean element with
a solution of biodegradable
soap and water, let dry and reinstall element.
ENGINE TIMING CHECK AND DISTRIBUTOR CHECK
(SOME MODELS)*$
- 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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18. EVAPORATIVE CONTROL SYSTEM (ECS) INSPECTION* -
Check all fuel and vapor lines and hoses for proper hookup, routing,
and condition. Check that
the purge valve works properly, if equipped.
Replace as needed.
19.
SHIELDS AND UNDERHOOD INSULATION
INSPECTIONAV
- Inspect shields and underhood insulation for
damage or looseness. Adjust or replace as required.
system installation
to see that gaskets are sealed properly and all hose
connections, fasteners, and other components are tight. Also check to
be sure that the air cleaner housing is properly seated, that
the cover fits
tightly, and
the wing nuts are tight. Tighten connections and fasteners
or replace damaged parts
as required.
20. AIR INTAKE SYSTEM INSPECTIONAV - Check the air intake
2 1. THERMOSTATICALLY CONTROLLED ENGINE COOLING
FAN INSPECTIONAV
- (If so equipped.) Inspect all hoses and
ducts for proper hook-up. Be sure the valve works properly.
22. EXHAUST PRESSURE REGULATOR VALVE INSPECTION”
- Check that the valve works properly. Correct any binding. Inspect
hoses for cracks, chafing
or decay. Replace parts as needed.
23. TIRE AND WHEEL ROTATION AND INSPECTION - For
proper wear and maximum tire life, rotate tires at the first
6,000 miles
( 10 000 kilometers) for Schedule I (+) or 7,500 miles (1 2 500
kilometers) for Schedule IT (0) and then every 15,000 miles (25 000
kilometers) thereafter. Follow the instructions and patterns shown in
Section 6. Check tires for uneven wear or damage. If irregular or
premature wear is apparent, check wheel alignment. Also, check or
damaged wheels. See “Tires”
in the Index for more information.
For dual wheels, whenever the vehicle, wheels, or fasteners are new,
have the wheel fastener torque set at the first
100, 1,000 and 6,000
miles (1 60, 1600 and 10 000 km).
Block the tires opposite those being removed to keep the vehicle from
rolling.
‘i: An Emission Control Service
ANoise Emission Control Service
VApplicable only to vehicles sold
in the United States
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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.
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Owner Checks and Services
Listed below are owner checks and services which should be made at the
time period specified to help ensure proper safety, emission performance,
and dependability
of your vehicle.
Be sure any necessary repairs are completed at once. Whenever any fluids
or lubricants are added to your vehicle, make sure they are
the proper ones,
as shown
in this Section.
At Least Once a Month
Tire inflation pressure check - Check the tires for proper inflation. If
they are low, inflate them to the level specified on the Certification/Tire
label. See “Loading Your Vehicle” or “Inflation-Tire Pressure”
in the Index.
At Least Once a Year
Key lock cylinder lubrication - Lubricate key lock cylinders with engine
oil. See
the “Recommended Fluid and Lubricants” chart in this section.
Transmission neutral or clutch start switch operation -
1. Before you start, be sure you have enough room around the vehicle.
2. Firmly apply both the manual parking brake and the regular brake. See
“Brakes” and “Parking Brake”
in the Index. Do not use the accelerator
pedal.
3. Be ready to turn off the engine immediately if it starts.
4. On automatic transmission vehicles, try to start the engine in each gear.
The starter should work only
in “P’ (Park) or “N” (Neutral).
On manual transmission vehicles, put the shift lever
in “N” (Neutral), push
the clutch down halfway, and try to start the engine. The starter should work
only when the clutch
is pushed down all the way to the floor.
Steering column lock operation - While parked, try to turn the key to
LOCK in each gear shift position.
With an automatic transmission, the key should
turn to LOCK only when
the gear shift
is in “P” (Park).
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On vehicles with a key release lever, try to turn the key to LOCK without
pressing the lever. The key should turn to
LOCK only with the key lever
depressed.
On
all vehicles, the key should come out only in LOCK.
Parking brake and transmission
“P” (PARK) mechanism operation -
I
Park on a fairly steep hill, with the vehicle facing downhill. Keeping your
foot on the regular brake, set the manual parking brake.
To check the parking brake: With the engine running and the
transmission
in “N” (Neutral), slowly remove foot pressure from the
regular brake pedal. Do this until the vehicle is held by the parking
brake only.
0 To check the “P’ (Park) mechanism’s holding ability: Apply the regular
brake and shift to
“P’ (Park). Release the manual parking brake, then
slowly release the regular brake.
Lap and Shoulder Belts Condition and Operation - Inspect belt system,
including webbing, buckles, latch plates, retractors, guide loops and
anchors. Have
a belt assembly replaced if the webbing has been cut or
otherwise damaged.
Body Lubrication Service - Lubricate all body door hinges with engine
oil. Also lubricate the tailgate, tailgate handle pivot points, and tailgate
mounted spare tire carrier
(if equipped}. Lubricate the body hood, fuel door
and rear compartment hinges, latches and locks including interior glove box
and console doors, and any folding seat hardware. Lubricate the hood safety
lever pivot and prop rod pivot. More frequent lubrication may be required
when exposed to a corrosive environment.
Periodic Maintenance Inspections - Listed below are inspections and
services which should be performed at least twice
a year (for instance each
spring or fall). You should
let your GM dealer’s service department or other
qualified service center do these
jobs. Make sure any necessary repairs are
completed at once.
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Steering and Suspension Inspection? - Inspect front and rear suspension
and steering system for damaged, loose
or missing parts, signs of wear or
lack
of lubrication. Inspect power steering lines and hoses for proper
hook-up, binding, leaks, cracks, chafing, etc. Lubricate the steering linkage.
Accelerator Control System - On gasoline engines, lubricate the pivot at
the
TBI throttle lever stud with engine oil. Do not oil any accelerator or
cruise control cables. Replace any cables that have high effort
or excessive
wear.
Exhaust System Inspection - Inspect the complete system including the
three-way catalytic converter. Inspect the body near the exhaust system.
Look for broken, damaged, missing or out-of-position parts,
as well as,
open seams, holes, loose connections or other conditions which could cause
a heat buildup in
the floor pan or could let exhaust fumes seep into the
passenger compartments.
Drive Axle Service? - Check readfront axle fluid level and add as needed.
Check constant velocity joints and axle seals for leaking.
I-- ~ lsfer Case (Four-wheel Drive) Inspection? - Every 12 months or at
oil change intervals, check front axle and transfer case and add lubricant
when necessary. Oil the control lever pivot point and all exposed control
linkage. Check vent hose at transfer case for kinks and proper installation.
More frequent lubrication may be required
on heavy-duty or off-road use.
?'A fluid loss in these systems may indicate a problem. Have them inspected
and repaired at once.
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