1994 GMC SIERRA Owners Manual

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
7-13
ProCarManuals.com

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
7-14
ProCarManuals.com

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
7- 15
ProCarManuals.com

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.
TO41 OR091
0
7-16
ProCarManuals.com

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
1Tr0911
7- 17
ProCarManuals.com

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.
7-18
ProCarManuals.com

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.
7-19
ProCarManuals.com

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.
7-20
ProCarManuals.com