GMC 1995 Safari Owner's Manual page 217

You should also use the proper viscosity oil for your vehicle, as shown in
the following chart:
RECOMMENDED SAL VISCOSITY GRADE ENGINE O I L S
FOR BEST FUEL ECONOMY AND COUl STARTING, SELECT THE LOWEST
SAL UlSCOSRY GRADE OIL FOR THE EXPECTED TEMPERATURE RANGE.
HOT
WEATHER
COLD
WEATHER
-
SAE
I
low-
LOOK
FOR THIS
SYMBOL
130
SAE
sw-30
PREFERRED
IF NEITHER
SAE
5W-30 NOR SAE IOW-30
GRADE OILS ARE AVAILABLE, SA€ 30
GRADE MAY BE USED AT TEMPERATURES
ABOVE 40 DEGREES F (4 DEGREES C)
GRADE OIL NOT RECOMMENDED
DO NOT USE SA€ 2OW-50 OR ANY OTHER
As shown in the chart, SAE 5W-30 is best for your vehicle. However, you
can use SAE 1OW-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.
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