Chevrolet 2009 Kodiak Owner's Manual page 232

What Kind of Engine Oil to Use
Look for three things:
5-30
•
CJ-4
Oils designated as API CJ-4 are required for the
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.
•
SAE 10W-40 or SAE 15W-40
SAE 10W-40 or SAE 15W-40 is best for the
vehicle. When it is very cold, below 0°F (−18°C), 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-30
or SAE 20W-50.