Originally Posted by rrounds

Rotella and Delo(15/40) is all I ran in my old R6. I run M1 high mileage 10/40 in my S with a can of MoS2. We have a little more miles on our S than you but if I had to change oil on one of our trips and they had Rotella 15/40 but not the M1 high mileage, the Rotella 15/40 would go in and I wouldn't think twice about it. If it can take the abuse of my 14k+ rpm R6 it will work just fine in my S. Plus Rotella works great in 500+ hp, 2000 LBS FEET of Tq turbo charged diesel engines, it will work just fine in the S. Rotella and Delo are very robust oils.

ROD