Hello, This is my first post and I'd just like to say that I've learned alot by coming here. I have alot to learn. I'd love a crash course if anyone is interested. Anyway, my real question is that I have an 05 Audi S4 and want to use GC 0W-30. I was going to try Motul E-Tech 0W-40 but the AZ near me carries the GC so I figured I'd try it. I was using Pentosynth 5W-40 and my dealer switched out to Agip Synthetic PC 5W-40. Is this a true synthetic? Is it good? Is it PAO or ester based? I want to do an oil change tonight and want to get some GC if you guys think it would be good. The engine is a 4.2L V8. It will be combined Hwy/cty and some aggressive driving, too. Thanks alot!