1994 GMC SIERRA engine

GASOLINE ENGINES WITH HEAVY DUTY EMISSIONS
- MAINTENANCE SCHEDULE lh- (continued)
THE SERVICES SHOWN ON THIS CHART UP TO 60,000 MILES (1 00 000 km) ARE TO BE
DONE AFTER 60,000 MILES AT THE SAME INTERVALS.
TO407
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DIESEL ENGINES - MAINTENANCE SCHEDULE yf
20 Air Intake System InspectionAB t t
21 Thermostatically Controlled Engine
Cooling Fan CheckAW-Every
t t
12 Months or
Inspection*
22 Exhaust Pressure Regulator Valve
23 Tire and Wheel Rotation**
t
24 Drive Axle Service** t t t +
25 Brake Systems Inspection**
A Change filter every 15,000 miles (24 000 km), except when op\
erating
in dusty
conditions. Dusty conditions may require more frequent filter re\
placement. Extreme
dust and dirt operating conditions (off-road), may require the air \
filter to be checked as
often as every 300 miles (483 km) and replaced as necessary.
* An Emission Control Service
** See “Explanation of Scheduled Maintenance Services” in this section.
A A Noise Emission Control Service
1 Applicable only to vehicles sold in the United States
t This maintenance schedule applies to all diesel engines available.
T0408/T0908
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DIESEL ENGINES - MAINTENANCE SCHEDULE
(continued)
If your driving conditions do NOT meet those specified in “Scheduled Maintenance Services”’\

in this section, use Maintenance Schedule II (e).
THE SERVICES SHOWN ON THIS CHART UP TO 60,000 MILES (100 000 km) ARE TO BE
DONE AFTER 60,000 MILES AT THE SAME INTERVALS.
T0409R0909
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DIESEL ENGINES - MAINTENANCE SCHEDULE I@
* An Emission Control Service
** See “Explanation of Scheduled Maintenance Services” in this section.
A A Noise Emission Control Service
Applicable only
to vehicles sold in the United States.
t This maintenance scheduled applies to all diesel engines available.
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0
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DIESEL ENGINES - MAINTENANCE SCHEDULE lh
(continued)
If your driving conditions do NOT meet those specified in “Scheduled Maintenance Services”\

in this section, use Maintenance Schedule
II (a).
THE SERVICES SHOWN ON THIS CHART UP TO 60,000 MILES (100 000 km) ARE TO BE
DONE AFTER 60,000 MILES AT THE SAME INTERVALS.
TO41
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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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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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