Hello - I recently read a thread on one of the diesel sites I frequent regarding the new CJ-4 Low Emission oil formulated for the new OTR diesel engine with catalytic converters and pre-mature engine wear on older diesel engines with flat tappets. From what I have read, the oil manufactures have removed ZDDP from the CJ-4 oils which was a key anti-wear compond used in previous API rated oils. Have any of you heard of this?

Thanks,
C. D. Hunter

Yes, I have been alerted to the newest oil changes and briefly mentioned it on one of the earlier "Diesel in 2014" posts.
So far you can still get earlier designated oils in single weight viscosity that is OK but be aware, the latest SM and the diesel equivalent C? are not adequate for the older engines. Looks like we're going to be needing to add additives if running the late oils. Beware that in spite of all the advertising hype on the oil container labels, only the API designation counts.

Attached is the article that first alerted me to the issue.

The only oil I will use in my 7 diferent diesel powered equipment and other large gas engines is Mobil Delvac 15-40 I have used Delvac for over 30 years and I can say I have never had an oil related failure.
Also Mobil Delvac is recomended buy manufacture for use in Cat, Cummins, and most others.
Just my 2 cents worth.
Russell

You think the new oil for the '07 engines is bad, just wait till the new oils that will have to be used in the 2010 engines come out. The only way I would run the CJ-4 oil in my older stuff would be to put in an additive like Lucas or something similar. The new CJ-4 oils is what is labeled as "low ash oil". Some of the original coponents that helped with extreme pressure loading (lubricity or film strength) in the CI-4 oils is what was causing this "ash" so it had to be removed. This "ash" is what is supposedly going to plug the Diesel Particulate Filters and the Catylists. Technology sure is great! I would start to expect more and more synthetic compounds added to conventional oils.

Rep0144,
Better check that API rating....those old standbys are no more. All of them are changing.

By the way OM, that is a neat article. That is the first time I had seen that one.

Mobil Delvac 1300 still labled as of the last 55gal barrel I bought a month ago API Service CI-4, CH-4, CG-4 CF-4, CF/SL, SJ
Russell

Your still good there....with old stock. When you get to CJ/SM that's when the formulation changes to where it makes a difference. Even the SL has reduced ZDDP but not severe enough for concern.

Coincidentally, I just bought 5 gallons of Diesel oil for my gas 22.This is the first time I have done this and have not put any in my 22 yet. Is it ok to run diesel oil in my gas tractor? The rating is CF. I bought it in bulk because the price of automotive oil in quarts has gone up so high. Thanks Old Magnet for publishing that article, I learned alot from it. - Wally

You should be fine with the CF rated oil.