1993 GMC SIERRA service interval

MAINTENANCE SCHEDULE It
If your driving conditions do NOT meet those specified in “Scheduled
Maintenance Services” in this section, use Maintenance Schedule
II (4.
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.
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MAINTENANCE SCHEDULE Ilt
If your driving conditions do NOT meet those specified in “Scheduled
Maintenance Services” in this section, use Maintenance Schedul\
e
II h),
54 57 60
90 95 100
.e
e e
e
e
e
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.
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MAINTENANCE SCHEDULE It
If your driving conditions do NOT meet those specified in “Scheduled
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.
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MAINTENANCE SCHEDULE Ilt
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.
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Scheduled Maintenance Services
Explanation Of Scheduled Maintenance 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 ve\
hicle.
1.
ENGINE OIL AND OIL FILTER CHANGE* -ALWAYS USE SG OR
SGKE QUALITY, ENERGY CONSERVING II 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, propshaft splines (2 wheel drive), 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 1, or every 3,000
(5000 km) for Maintenance Schedule 2.
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 -Lubricate the clutch fork
ball stud through the fitting on the clutch housing. Lubricant must be
added “sparingly” to the fitting, as only.
0066 Ib. (.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. ENGINE IDLE SPEED ADJUSTMENT (DIESEL ENGINES)* -Adjust to
the specifications shown on the underhood label. You must use
calibrated test equipment.
5. 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
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6. 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\
.
7. 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.
8.
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.
Where the outside temperature regularly reaches 90°F (32°C\
) or
higher.
In hilly or mountainous terrain.
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
8600 GVWR or every
24,000 miles (40 000 km) for vehicles over 8600
GVWR. See “Automatic Transmission Fluid” in the Index for more
information.
Manual Transmission -Transmission fluid does not require periodic
changing.
Regulator Valve System for any worn, plugged or collapsed hoses. Have
the system checked as described in the Service Manual.
9.
CDRV SYSTEM INSPECTION* -Check
the Crankcase Depression
10. FUEL FILTER REPLACEMENT* -Replace the fuel filter at the specified
interval
or sooner if clogged.
11. SPARK PLUGS REPLACEMENT* -Replace spark plugs with the type
listed in Section
6. See “Specification Charts” in the Index.
12.
SPARK PLUG WIRE INSPECTION* -Clean wires and inspect for burns,
cracks or other damage. Check the wire boot fit at the distributor and at
the spark plugs. Replace wires as needed.
*An Emission Control Service
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Scheduled Maintenance Services
Periodic Maintenance Inspections
Listed below are inspections and services which should be perfo\
rmed 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.
Steering and Suspension lnspectiont -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. (On vehicles equipped wit\
h manual
steering gear, check for seal leakage.) Lubricate the steering linkage.
Accelerator Control System -Lubricate all pivot points with engine oil,
except the
TBI throttle shaft. Remove all external deposits from the injector
pump face cam on 6.2L and 6.5L engines.
Do this when the engine is cold
and not running.
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.
Transfer Case (four-wheel drive) lnspectiont -Every 12 months or at oil
change intervals, check front axle and transfer case and add l\
ubricant when necessary. Oil the control lever pivot point and all exposed c\
ontrol linkage.
Check vent hose at transfer case for kinks and proper installa\
tion. More
frequent lubrication may be required on heavy-duty or off-road use.
tA fluid loss in these systems may indicate a problem. Have them inspected
and repaired at once.
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