• Light Duty Emission Vehicles-Change oil each
12 months or 7,500 miles. If more than 7,500 miles are
driven in a 12 month period, change oil each 7,500 miles.
• Heavy Duty Emission Vehicles-Change oil each 4
months or 6,000 miles. If more than 6,000 miles are
driven in a 4-month period, change oil each 6,000 miles.
• Change oil each 3 months or 3,000 miles (2
months or 3.000 miles on Heavy Duty Emission
Vehicles), whichever occurs first, under the following
conditions:
—Driving in dusty conditions.
—Trailer pulling or camper use.
—Motor Home use.
—Extensive idling.
—Short-trip operation at freezing temperatures
(engine not thoroughly warmed-up).
• Operation in dust storms may require an
immediate oil change.
• For Light Duty Emission Vehicles replace the oil
filter at the first oil change, and every second oil change
thereafter, if mileage (7,500 miles is the determining
factor. If time (12 month) is the determining factor, then
change oil filter with every oil change. For Heavy Duty
Emission Vehicles, replace the oil filter at the first oil
change and every other oil change thereafter using 6,000
miles or 12 month as the determining factors. AC oil
filters (or equivalent) provide excellent engine protection.
The above recommendations apply to the first
change as well as subsequent oil changes. The oil change
interval for the engine is based on the use of SE oils and
quality oil filters. Oil change intervals longer than those
listed above will seriously reduce engine life and may
affect the manufacturer’s obligation under the provisions
of the New Vehicle Warranty.
A high quality SE oil was installed in the engine at
the factory. It is not necessary to change this factory-
installed oil prior to the recommended normal change
period. However, check the oil level more frequently
during the break-in period since higher oil consumption
is normal until the piston rings become seated.
NOTE: Non-detergent and other low quality oils
are specifically not recommended.
Oil Filter Type and Capacity
• Throwaway type, 1 quart U.S. measure, .75 quart
Imperial measure.
• 250 and 292 cu. in., AC Type F-25. 305, 350,
400 and 454 cu. in., AC Type F-35.
Crankcase Capacity (Does Not Include Filter)
• 292 L6 Engine; 5 quarts U.S. measure, 4.25
quarts Imperial measure.
• All other engines; 4 quarts U.S. measure, 3.25
quarts Imperial measure.
Recommended Viscosity
To help assure good cold and hot starting, as well as
maximum engine life, fuel economy, and oil economy,
select the proper oil viscosity for the temperature range
anticipated from the following chart:
____________SOW 20. 20W 40 ? 0w 50
l I I I I
• lo w 30. lo w 40
..........
I I I I
°F -2 0 0 20 40 60 80 100
C -3 0 20 -1 0 0 10 20 30 40
Temperatu re Range Antic pated Before Next Oil Change
NOTE: SAE 5W -30 oils are recommended for all
seasons in vehicles normally operated in Canada.
SAE 5W -20 oils are not recommended for
sustained high-speed driving.
Checking Oil Level
The engine oil should be maintained at proper level.
The best time to check it is before operating the engine
or as the last step in a fuel stop. This will allow the oil
accumulation in the engine to drain back in the
crankcase. To check the level, remove the oil gauge rod
(dipstick), wipe it clean and reinsert it firmly for an
accurate reading. The oil gauge rod is marked "FULL"
and "ADD". The oil level should be maintained in the
safety margin, neither going above the "FULL" line nor
below "ADD" line.
NOTE: The oil gauge rod is also marked "Use SE
Engine Oil" as a reminder to use only SE oils.
Supplemental Engine Oil Additives
The regular use of supplemental additives is
specifically not recommended and will increase operating
costs. However, supplemental additives are available that
can effectively and economically solve certain specific
problems without causing other difficulties. For example,
if higher detergency is required to reduce varnish and
sludge deposits resulting from some unusual operational
difficulty, a thoroughly tested and approved additive -
"G.M. Super Engine Oil Supplement" (or equivalent) - is
available.
Drive elts
Drive belts should be checked every 7,500 miles or
12 months (6,000 miles or 4 months Heavy Duty
Emission Vehicles) for proper tension. A loose belt will
affect water pump and generator operation.
Positive Crankcase Ventilation Valve (P.C.V.)
Every 30,000 miles (24,000 miles Heavy Duty
Emission Vehicles) or 24 months the valve should be
replaced. Connecting hoses, fittings and flame arrestor
should be cleaned. At every oil change the system should
