I think that Rotella T Synthetic diesel oil you speak of is really a
5w40. There is a Rotella conventional diesel oil in 15w40. I sometimes
use both of these in my diesel Vanagons. I just put some in one today
after changing the head, JX 1.6TD.

Mark

Mike S wrote:

> At 06:11 PM 9/13/2007, Todd Last wrote...
>
>> I thought you were not supposed to run SM rated oils because of the
>> lack of zinc additive?
>
>
> Shell Rotella T "Synthetic" (actually, a Group III, hydrocracked
> petroleum basestock) 15W-40 is available for fairly cheap at
> Wally-world (~$14/gallon). Although marketed as a diesel oil, it also
> carries an SL/SJ/SH (but not SM) rating. http://tinyurl.com/2ms42g
>
> VW approves a 15W-40 to the same max temp as a 20W-50, but you also
> pick up some extension on the low temp end.
>