Just wondering. My SS came from SLP, who builds the SS's, with the Castrol Syntec Package, which meant every fluid in the car was Castrol Synthetic. I only ran that junk in the car for 500 miles, just to let it break in. I then switched over to Mobil 1, because that is what I used in all my previous F-bodies, and had great luck with it. I had been doing alot of reading, and read several good things about teh Vlavoline Synthetic, so I gave it a shot, and picked up almost 10psi of oil pressure @WOT!

Needless to say, I'm still running the Valvoline in the SS. I've always ran an AC Delco filter though.

The transmission and rear-end have Redline.
Now, onto the 240. It's a 93' auto car that my wife drives approx. 50 miles roundtrip, everyday. The previous owner had been using Havoline conventional oil, and just a cheap filter. I'm about to change the oil and filter, and was wondering what the majority of most people here are using.
Thoughts and opinions are appreciated.
