Sandy,
Have you done the math, is using Mobil 1 cheaper than regular oil, using extended drain intervals?

FWIW: I've run 3 VW Diesels to high mileage (my '91 has 237,000 on it), using just name-brand 15w-40 oils. I had
occassion to measure the crank and cylinders on the '85 Golf when it had about 200,000 miles on it and everything was right at "stock".

Whatever you do, additives such as STP, Slick 50, etc. should NOT be used. They're pretty much useless and can even be harmful.

<<Jim>>

Sandy Noyes wrote:

> Chuck -
>
> I use Mobil 1 in my Toyota Celica which now has 150,000 miles on it. The engine is as clean as a whistle. I
> change oil every 25,000, change filter every 5,000 and top up a\oil as neccessary. I am switching to Del-Vac
> (the Mobil diesel synthetic) in my '94 Ram turbo Cummins at the next oil change. I should be able to go all
> year plenty OK. I know many people disagree with this. That's OK. I can only say that all the cars I have
> used Mobil 1 in have gone to the 150,000 mile mark with no engine damage, using the 25,000 oil change,
> 5,000 filter change schedule. According to Mobil
> (http://www.mobil.com/business/cvl/onhighway/product_services/delvac1/index.html) this is OK. YMMV. I
> feel comfortable with this.
>
> Check out the web address and make up your own mine. BTW, I have been using Mobil 1 for 20 years.