GMC 2003 C4C042 Owner's Manual page 283

D
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SAE 15W 40
As shown in the viscosity chart, SAE 15W
best for your vehicle. However, you can use SAE
-
10W 30 at temperatures above 0
When it's very cold, below 0
-
use SAE 5W 40 to improve cold starting.
These numbers on the oil container show its
viscosity, or thickness. Do not use other viscosity
oils such as SAE 10W
You should look for this on the oil container, and use
only those oils that display the logo.
GM Goodwrench R oil of the recommended viscosity
grades meets all the requirements for your vehicle.
-
40 is
_ _
-
F ( 18 C).
_ _
-
F ( 18 C), you should
- -
40 or SAE 20W 50.
-
This doughnut shaped logo
(symbol) is used on most
oil containers to help you
select the correct oil. It
means that the oil has been
certified by the American
Petroleum Institute.
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