Carl,
Shell RotellaT is very popular with truckers. I've run it, along with a mix of
other oils in VW Diesels with good success; my Jetta has 239,000 miles on it
and still runs like new. Two previous VW Diesels went 200,000+ miles w/o
problems also.

One of the main claims to fame with synthetic oils is slightly better fuel
economy due to the lower viscosity. Mobil claims 3-4% better, on average. The
other benefit is extended drain intervals, which makes up for the higher cost
of the oil.

<<Jim>>

Carl Johnson wrote:

> Is it and option to use Synthetic oil in a Chev. Diesel eng.? and at the
> same time I want to ask the question about brand names of diesel oil (Shell
> rotola) or (Oilsum brand) does one over the other make a difference.