Question about CJ-4 oils??

[Ponch]

I have a an early 2007 duramax pickup....which does not call for CJ-4 oils, due to not having the newest DPF emission system....so it's obvious that the newest CJ-4 oils compared to CI-4 oils contain much less zinc/phosphosus...ZDDP, so what is added to these newest oils to make up for less ZDDP? Do duramax engines have flat-tapped lifters?? If not....i would not worry much about new CJ-4 oils much....help me sleep at night oil guru's please! I want to feed this truck the best that I can! Do CI-4 oils exist anymore other than amsoil's 15w40 marine/diesel truck oil which I believe is still CI-4?

 

[Johnny]

No need to worry, sleep well. Use your favorite CJ-4 oil and enjoy the truck. It has more than enough ZDDP in it.

 

[Jim Allen]

I agree. You are focusing on only one element in the oil, ZDDP, and not considering all the other advancements made in the development of CJ-4 which, in many ways, is a better formulation than CI-4. CJ-4 oil makes even more sense when you are using ULSD. All data indicates that CJ-4 has more than enough ZDDP to protect your engine. I would not use CJ-4 if you are still using LSD (the 500ppm sulphur variety) because that's when CJ-4 wouldn't be up t protecting your engine from acid buildups but I think it's pretty hard to find now and only in off-road applications. Even my farm fuel supplier has gone over to ULSD now, so I've been running two old tractors on ULSD/CJ-4 and the used oil analysis are fine. An older diesel pickup too.

The Duramax has roller lifters, by the way, which do quite well on lower levels of ZDDP.

 

[daman]

Sleep well a CJ oil will protect it just fine,no worries my son.