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Shell Rotella T4 10W30 has the new Ford rating. I believe any CK4/SM rating will meet Ford's specification since API SM doesn't require Phos. to be less than 1,000ppm which is where Ford want it to be. On the other hand CK4/SN requires Phos. to be less than 800ppm and that's the issue.
Upon closer read of the Ford statement, I believe that you are correct. 10w-30 CK-4/SM is OK. But 10w-30 CK-4/SN is NO GOOD.
I use Valvoline Blue in my Volvo diesels in my boat and have an analysis done every 100 hours. It is never broken down to where it needs replaced. I replace it at 100 but....... That's what I'm running in the truck now as well.