Originally Posted By: wdn
Thanks for that jfairchild327. CK-4 oil works great in the oldest Power Stroke diesel so then it should work well in all of them including the 6.7 L. The CK-4 paranoia on these forums borders on mass hysteria.
I would not call it mass hysteria, I would more likely call it Ford talking out of both sides of their mouth and when coupled with the potential loss of warranty on a $60-80K truck, it seems prudent for 6.7L PSD owners to take a pause.
For clarity, let us review what Ford has done:
1. About 1 month before CK-4 oils were to hit the market Ford creates a brand new specification for Powerstroke approved oil which superseded the standing specification and for which there were no oils on the market that met the specification (at the time).
2. Ford would not (and still has not) disclose the test criteria for meeting the new specification and/or what engine parts would see extra wear by using CK-4 oils.
3. Ford then stated that CK-4 oils need to have >1000PPM of phosphorus to prevent long term rocker arm wear, but then proceeded to approve CK-4 oils that have
With all of that said, it is no wonder that PSD owners are confused and/or are overly cautious. As someone who owns one of these trucks still under warranty, I simply stocked up on CJ-4 oil and called it a day.