Chevrolet Kodiak 2008 Owner's Manual page 234

What Kind of Engine Oil to Use
Look for three things:
•
CJ-4
Oils designated as API CJ-4 are required for your
vehicle. The CJ-4 designation can appear either
alone or in combination with other American
Petroleum Institute (API) designations, such as API
CJ-4/SL. These letters show API levels of quality.
Notice: Use only engine oils that have the
designation CJ-4 for the diesel engine. Failure to
use the recommended oil can result in engine
damage not covered by your warranty.
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