have done oil changes with Mobil 1; will try GC for next one. Just picked up 6 quarts for $38 (inc tax) - $5 autozone gift card. i think the offer is until mid-Nov.

as an aside, just touched up my 8th rock chip! WTF! I have a clear bra on the front as well as side mirrors; these rock chips are on the trunk and side -- this last one was on the roof!! kash