GMC 1997 Safari Owner's Manual page 269

RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT
THE
LOWEST
SAE VISCOSITY GRADE OIL FOR THE EXPECTED TEMPERATURE RANGE.
HOT
WEATHER
WOK
FOR T H I S
SYMBOL
I -
m- 1
SA€ 1OW-30
SAL 5W-30
[m
PREFERRED
COLD
WEATHER
00 NOT USE SAE 2OW-50 OR ANY OTHER
GRADE OIL NOT RECOMMENDED
As shown in the chart, SAE 5W-30 is best for your
vehicle. However, you can use SAE low-30 if it's going
to be 0°F (-18°C)
or above. These numbers on an oil
container show its viscosity, or thickness. Do not use
other viscosity oils, such as SAE 20W-50.
I
NOTICE:
~-
Use only engine oil with the American Petroleum
Institute Certified For Gasoline Engines
"Starburst" symbol. Failure to use the
recommended oil can result in engine damage
not covered by your warranty.
GM Goodwrench@ oil meets all the requirements for
your vehicle.
If you are in an area where the temperature falls below
-20°F (-29"C), consider using either an SAE 5W-30
synthetic oil or an SAE OW-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.