I'm not out trying to prove some point about synthetics, but I have a side-by-side comparison that you guys might find interesting. I maintain my female friends 4cyl turbo Audi now and found the valvecover and dipstick to be clean, in a like-new condition. I asked her what she has done over the last 5 years/60k for oil. "Mobil 1 every year" she said proudly. He ex is a BMW guy, I guess he suggested it. I thought, "all that will change".
Oddly her brother-in-law lives across the street and bought a similar *used* car, very low miles -in the teens. He knew the owner took only a 1 mile daily commute in it, her office was in-sight of her home. Dealer inclusive-service dictated 5000 mile (V6 had 7500 mile intervals, maybe this car had the longer interval, essentially once-a-year also) changed with Castrol GTX 15w-40 it's the dealer pick. I said, "how about seeing a snapshot of what dealer oil and short commutes does"... I pulled the dipstick, it had the most thick varnish I have ever seen in a modern car and was totally pitted, deeply. He was shocked, only a 20k mile car at this point. So, Mobil 1 did the job. Dealer Dino did not. Just a thought. I have changed out completely to synthetic on all 6 cars I maintain. Rotella Synth is my poison.
[ October 06, 2003, 11:14 PM: Message edited by: TSoA ]