Explanation Of Maintenance Schedule - GMC 1976 ZEO 6083 Maintenance Manual

EMISSION CONTROL MAINTENANCE (1975 AND 1976 CERTIFIED ENGINE)
*To determine year engine was certified, refer to emission control decal on engine valve cover.
EXPLANATION OF MAINTENANCE SCHEDULE
Presented below is a brief explanation of each of
the services listed in the preceding Maintenance
Schedule .
Vehicle operation under conditions such as heavy
dust, continuous short trips, use of other than un-
leaded or low lead fuels or pulling trailers, is not
considered normal use and therefore more frequent
maintenance will be required . Such additional
maintenance requirements are included where appli-
cable.
ITEM
NO. SERVICES
LUBE AND GENERAL
MAINTENANCE
1 CHASSIS-Lubricate all grease fittings in front
and rear suspension and steering linkage. Also lubri-
cate transmission shift linkage, brake pedal spring,
parking brake cable guides and linkage.
2 ENGINE OIL-Change each 3 months or 3,000
miles, whichever occurs first.
3 FLUID LEVELS-Check level of fluid in brake
master cylinder, power steering pump, all batteries,
engine, final drive, transmission, and windshield
washer . The engine coolant should be checked for
proper level and freeze protection to at least -20°F.
(-29°C .) (-37°C . in Canada), or to the lowest tempera-
ture expected during the period of vehicle operation.
Proper engine coolant also provides corrosion pro-
tection.
Any significant fluid loss in any of these systems
GENERAL INFORMATION
0- 7
or units could mean that a malfunction is developing
and corrective action should be taken immediately.
A low fluid level in the brake master cylinder front
reservoir could also be an indicator that the disc
brake pads need replacing.
4 AIR CONDITIONING-Check condition of air con-
ditioning system hoses and refrigerant charge at
sight glass. Replace hoses and/or refrigerant if need
is indicated.
5 AIR COMPRESSOR-Filter should be washed
with soap and water solution or replaced .
6 TIRES-To equalize wear, rotate tires as illus-
trated in Section 10 and adjust tire pressures as
shown on tire placard on glove box door . Have
wheel-nut torque checked after 1st 500 miles and 500
miles after every wheel replacement thereafter.
7 ENGINE OIL FILTER-Replace at the first oil
change and every 2nd oil change thereafter.
8 AUTOMATIC TRANSMISSION FLUID AND FINAL
DRIVE LUBRICANT-Change the transmission fluid
and filter ; change final drive lubricant.
9 COOLING SYSTEM-At 12-month or 12,000-mile
intervals, wash radiator cap and filler neck with
clean water, pressure test system and radiator cap for
proper pressure holding capacity . (Tighten hose
clamps and inspect condition of all cooling and
heater hoses.) Replace hoses every 24 months or 24,-
000 miles or earlier if checked, swollen or otherwise
deteriorated .
At 1st 6 months or 6,000 miles -
then at 12 months/12,000 mile
35 Thermostatically Controlled Air
Cleaner - Check
intervals 36 Carburetor Choke - Check
37 Engine Idle Speed and Mixture Adjustment
38
Carburetor and Intake Manifold
Mounting Torque
Every 6,000 miles 39 Spark Plug Replacement
Every 12 months or 12,000 miles 40 Carburetor Fuel Filter Replacement
41 Thermal Vacuum Switch and Hoses - Check
42 PCV System - Check
43 Air Cleaner Element Replacement
44 Spark Plug Wires - Check
45
Engine Timing Adjustment and
Distributor - Check
46 Throttle Return Control - Check
Every 24 months or 24,000 miles 47 ECS System Check and Filter Replacement
48 Fuel Cap, Tanks and Lines - Check