Originally Posted by DVS99TRANS

Tell your mechanic that ummmm my car came stock with Mobil 1 5W-30. So did the camaros, all GM V8 trucks, CTS-Vs, GTOs, and all vettes. That means he is a GM engineer then. Say something like that, don't recommend going back to that retard if I where you If he has been putting conventional motor oil in your car, and you have any oil leaks. Blame him!!!

Originally Posted by SOMbitch

These cars came with Dino oil. Vettes and some Caddys got the Mobil. Not sure on the Goat and trucks. I don't think my Z-71 came with synth though.

Originally Posted by BriancWS6

If you want to use the Mobil 1 line, I suggest the 5w40 or the 0w40 over the 5w30 or 10w30. My recommendation however would be the Pennzoil Platinum 5w30, it's one of the best readily available oils for these engines.