How is SM rated oil different from SL?

Messages
1,346
Location
Lexington, NC
I have a Can Am RT with elect clutch. V-Twin 998cc. Handbook specifically cautions against useing SM as it will "harm the clutch". If the oil is also rated Jaso/MA, how can SM cause clutch problems? FWIW, they call for 3K mile oil and filters change. The elect clutch model uses a small filter in the transmission, and a larger one for the motor. Oil capacity is 4 1/2 with filters. They used to say filter change every other oil change, but modified that to every oil change. They also call for synthetic or semi/syn, so this gets pricy using Amsoil as I have been doing at $9.10 per quart. I had planned to switch to Rotella T6 but find that its rated SM.
 
Messages
4,998
Location
Milwaukee, WI
Well, the "energy conserving" SM oils contain less ZDDP. The heavier weight SM oils can contain the same amounts SL oils could. Using a 40 weight SM oil thats Jaso/MA should be fine.
 
Last edited:

JAG

Messages
5,320
Location
Fredericksburg, VA
Jaso MA requires the oil to cause a certain range of friction in a test. If they call for that spec and you find an oil that meets it AND API SM it is fine. Non-energy conserving API SM oils that do not meet JASO MA can contain a hefty dose of ZDDP which is good but they may have too much friction reducing additives to prevent clutch slippage.
 
Messages
1,069
Location
Florida /Texas
Amsoil at $9 is double the price, its also double the life of the rotella 5w40 via my analisys. You could run the AMF 15w40 diesil amsoil, might be cheaper but just as good.
 
Messages
6,388
Location
Washington St.
Can-Am probably is not considering Rotella. I think it is the only SM rated oil that is also rated JASO-MA. (Schaeffer #707 20W-50 is rated SN and JASO-MA.)
 
Top