I'm sure Solitaire (dealer?) wouldn't be using a full synthetic Castrol, probably Magnatec Pro?
I dumped the Amsoil 10w40 PP last night for M1 0w40, I'll see how it goes later on tonight.
Ex850R;70175 wroteI have said this before , my very low mileage 850R didn't like the mobil1 at all.
It worked better with castrol synthetic.
My later x70 turbo cars seem happier with mereril or semi synthetic although I am going to Penrite/Repco full syn for the V70R and see how it fares.
The whiteblock is certainly a finicky thing in many areas.
Was it burning oil (Mobil 1)? Or are are you talking "feel" or noise?