batman wrote on 12/06/17 at 09:12:31:JLC , I believe you're correct ,I think Dave is mistaken .
I think there is an apple/oranges thing going on here.
There was an "old" Rotella T6 that we had used for years, and it worked fine in the Savage. It was rated CJ-4 and was also MA rated for motorcycles. It came in the "old squatty" bottle.
Recently the "new" Rotella T6 came out and it was a reformulated version of the CJ-4 we had been using, and it is in the taller redesigned bottle. The amount of moly in the oil was increased, and some long term users of T6 started to experience clutch slippage issues. (If you can use this oil and not have a slippy clutch....great!)
And now comes along another grade of oil....a CK-4 rated synthetic oil.....and just to confuse us they are also calling this oil T6 even though they already have a T6. It is not yet available in any store or truck stop I have seen - it is in a shorter bottle than the CJ-4 rated T6....and evidently the only reason it is not rated for motorcycle use is that the exceeds the alowable limit of phosporous....but it is alright for use in wet clutches....and it has less moly than the CJ-4 rated T6. If you can find it - it is most likely going to be the better T6 for the Savage as it has less moly and more ZDDP.
So we can avoid this confusion in the future....what are you wanting to call the 3 versions of T6 to avoid more confusion? We have the "original" CJ-4 rated T6, the "new" reformulated CJ-4 rated T6, and a completely new CK-4 rated T6.