Chevrolet 1997 Astro Owner's Manual page 269

RECOMMENDED SAE VISCOSITY GRADE ENGINE OILS
FOR BEST FUEL ECONOMY AND COLD STARTING, SELECT THE LOWEST
S A E VISCOSITY GRADE OIL FOR THE EXPECTED TEMPERATURE RANGE.
HOT
WEATHER
"F
c
100
-
+80.
+ 6 0 .
+
4 0 .
+ 2 0 .
0 -
I
7
"C
t
38
t
21
t
16
t b
- 7
-
18
LOOK
FOR THIS
SYMBOL
COLD
WEATHM
DO 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
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.
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.
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