Originally Posted By: TiredTrucker
No, Dan hasn't said much in that regard. I will have to send him a text and find out what he knows. CK-4 allows for both XXw30 and XXw40 oils to be used, so I would expect them to offer both. FA-4 is strictly XXw30 spec.
The CK-4 spec will retain the >3.5 HTHS we currently have with CJ-4 , so it should fulfill the backward compatible goal. But I have not seen any appreciable data referencing how add pack components will differ. That will play into all of this.
The OEM's will never "slowly" approve of FA-4 oils in the older engines. From trade articles I have read on this, a engine has to have different internals that will compensate for the lower HTHS of FA-4 oils. FA-4 HTHS falls way below the minimum level of OEM recommendations for engines now. So any engine that will be "certified" for FA-4 oils will have to take care of itself more since the oil won't be doing it. Different ring and bearing metallurgy at a minimum. Pity the naive soul who puts a load of FA-4 in an older motor. You know that is going to happen sooner or later. Owners will have to stay on their toes and make sure it doesn't happen. What a fine mess our illustrious government has foisted on us.
Thanks for the reply, TT. I hope all is going well your way.
You nailed it right on the head, my thoughts exactly!
I can imagine it will also be a bit of an undertaking for maintenance shops to stock separate lubes for New Generation motors, and for older motors, -which does leave margin for error. I know I'll be watching which gets put into my motor like a hawk.
I've called Mobil Delvac's Technical Support line in the past on this subject, and was told pretty much the same thing your Supplier told you in regards to the CK-4 lubes, they will be fully backwards compatible. I also asked if the FA-4 lubes would somehow tweaked in the future to be backwards combatible, but the gentleman told me the specs for the FA-4 lubes weren't set in stone at that time.