Owner's manual, page 266 specifically says to run 5W30, which is what I've always run. For the later cars, GM changed the recommendation. It's still the same motor, but the "diatribe" is a good disclaimer since some clown will try to blame me if something goes awry and their manual states something different from what I used based on my manual...
Sheeeeesh. Whole diatribe about checking your manual to see what oil to run, and... you're running the wrong oil 😅
Owner's manual, page 266 specifically says to run 5W30, which is what I've always run. For the later cars, GM changed the recommendation. It's still the same motor, but the "diatribe" is a good disclaimer since some clown will try to blame me if something goes awry and their manual states something different from what I used based on my manual...