Chevrolet 10 Series 1968, Руководство по обслуживанию

Страница: 15 / 713

LUBRICATION 0-12
ENGINES (GASOLINE)
(10-30 SERIES)
ENGINE OIL RECOMMENDATIONS
Use only "fir s t line” oils which, according to the
label on the can, are (1) intended for service MS, and
(2) automotive manufacturer's tests (including General
Motors Standard GM 6041-M). The oil change interval as
recommended in this section on oils, is based on the
regular use of this quality of engine oil. The majority
of the suitable oils currently available are multi­
viscosity (e.g., 10W-30) products.
NOTE: Non-detergent and other low quality
oils are specifically not recommended. The use
of proper engine oils and oil change intervals
are your best assurance of continued reliability
and performance from your Chevrolet engine.
The use of ' ‘break-in” oils, “ tune-up” compounds,
“ friction-reducing” compounds, etc.., in your Chevrolet
engine are not recommended. However, there are addi­
tive supplements available that can be helpful under
certain conditions. For example if higher detergency is
required to reduce varnish and sludge deposits, a
thoroughly tested and approved concentrate—“ Engine Oil
Supplement” * —is available.
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 (dip stick),
wipe it clean and reinsert it firm ly for an accurate
reading. The oil gauge rod is marked “ F U LL” and “ ADD
O IL” . The oil level should be maintained in the safety
margin, neither going above the “ F U LL” line nor below
“ ADD O IL” line. Reseat the gauge firm ly after taking
the reading.
Ventilation Filter
Remove the crankcase ventilation filter (where used) at
each oil change (more often under dusty conditions), wash
in kerosene, re-oil with SAE 20W oil and reinstall.
Engine Oil Change Interval
Change engine oil each 4 months,(f) except that if more
than 6,000 miles are driven in a 4-month period, change
oil every 6,000 miles. This interval applies to the initial
change as well as subsequent oil changes. The oil change
interval for Chevrolet engines is based on the use of
oils that meet the requirements indicated in the section
on “ Engine Oil Recommendations.” Oil change intervals
longer than 4 months or 6,000 miles will result in serious
reductions in engine life and may effect Chevrolet’s
obligation under the provisions of the New Vehicle
Warranty.
Certain atmospheric and/or driving conditions in­
cluding prolonged operations at sub-zero temperatures
or under extremely dusty conditions, frequent trailer
hauling, and extensive idling necessitate more frequent
*or “ High Detergency Concentrate”
oil and filter changes.f Operation in dust storms may
require an immediate change of both oil and filter. See
your Chevrolet dealer for advice on frequency of oil and
filter changes because of unusual driving conditions.
A high quality MS oil meeting General Motors Standard
GM 6041-M was installed in your engine at the factory.
It is not necessary to change this factory-installed oil
prior to the recommended normal change period. How­
ever, the oil level should be checked more frequently
during the break-in period since somewhat higher oil
consumption is normal until the piston rings in the
engine become seated.
Recommended Viscosity
The following chart will serve as a guide in selecting
the proper oil viscosity. In addition to providing lubri­
cation, the correct viscosity helps assure good cold and
hot starting by reducing friction and thus increasing
cranking speed.
Anticipated Temperatures Viscosity Number
Above Freezing (+32°F.) SAE 20W, SAE 10W-30
Below Freezing and above 0°F. SAE 10W, SAE 10W-30
Below 0°F. SAE 5W, SAE 5W-20
NOTE:
When changing oil consider the antici­
pated temperatures for the next 4 months.
• SAE 5W and 5W-20 oils are not recommended
for sustained high speed driving.
• SAE 30 and SAE 20W-40 oils may be used at
temperatures above 90°F.
• SAE 5W-30 oils may be used at temperatures
below 32°F.
• SAE 10W-40 oils may be used at temperatures
between 0 and 90°F.
OIL FILTER REPLACEMENT
Replace filte r(f) at first oil change and at every second
oil change thereafter. This recommendation is based on
the use of engine oil which meets the requirements in­
dicated in the section on “ Engine Oil Recommendations,”
and the use of the applicable A.C. or equivalent quality
replacement oil filter.
40-80 SERIES
ENGINE OIL RECOMMENDATIONS
High quality engine oils are available at your Chevrolet
Dealer and at many service stations. It is recommended
that you use an oil which, according to the label on the
can, is (1) intended for service MS and (2) passes car
makers’ tests or meets General Motors Standard
GM-6041M. Oils conforming to these types contain deter­
gent additives.
t In many such situations, oil change intervals should not
exceed 2 months, or 3,000 miles, whichever occurs
first, and similarly, filter changes should not exceed
4 months or 6,000 miles, whichever occurs first.
CHEVROLET TRUCK SERVICE MANUAL