Join Date: Nov 2006
Location: Grand Rapids, MI
I run valvoline semi-synthetic and a wix filter in my Jeep, ditto on the GrandAm, and that worked well.
As for the 3100/3400 valve noise it didn't help a whole lot, but it might be a different noise on the ecotec.
For the supercharged ecotecs and some Corvettes, GM recommends mobil1 synthetic oil.
Amsoil and Royal Purple probably won't hurt, but are more expensive, so I wouldn't use these unless they're used in competition (which being a 4cyl/auto probably isn't)
-1993 Saturn SC2 manual *sold- 2004*
-2000 Pontiac GrandAm SE v6 *sold- 2006*
-1974 AMC Javelin 360v8, 4sp *underfunded project car*
-1996 Jeep Cherokee Country *DD with more uses than a swiss army knife*
-2007 Kawasaki EX650 *comfortable sportbike, summer dry driver*