I've seen this new rating around on a couple of threads. Even Terry mentioned this on another post.
Has this oil come out yet? What are the advantages/dis-advantages/difference of SM over SL rated oil?
Next summer for the 2004 model-year vehicles.
It'll meet tougher emission control requirements and probably offer better engine protection for the lease-return vehicles the car makers get back where the lessee has taken little or no care of the engine.