That article that someone posted about the longevity test with Mobil 1 is good enought for me. They decided to finally end the test at 20,000 miles...

I'm more comfortable about running it till 7500 miles in my car, or till the oil monitor in the buick hits 0% (~9000 miles)

either way, it seems I'm using about half the oils expected life. I would change less often due to oil filter life...



98 GL sport (V6 MTX) The Durable Duratec? - (DMD, Metal impeller WaterPump, Synth & Stinky in the tranny)