I remember talking to a diesel engine rebuilder a few years ago about oils. He told me the engines ran on Petro-can oils were cleaner and in generally better condition.
The motor oil bible rates P/C 5/40 number one in that viscosity and P/C also rates very high in other categories as well.
I was totally surprised to see P/C recommend this oil for motorcycle wet clutches! I have not seen this in any oil I've researched except for motorcycle specific oils.
Petro-can was Gulf oil who was BA oil.
Here are a couple quotes from the website.
" Wet Clutch Transmissions, including
motorcycles & all terrain vehicles
(meets performance requirements of
Gasoline Engines "
" DURON SYNTHETIC meets all the high temperature
physical property requirements of a
15W-40 according to SAE J300 and API CI-4. "
I would think this oil to be perfect for our temperature ranges with better cool weather protection.
Does anyone use this oil? How much does it cost?