It is fairly well known that lubricating oil manufacturers have been forced to reduce ZDDP from their gasoline engine-oil formulations because ZDDP is linked to CatCon failures.

I didn't know this until I wiped out all three solid lifter cams and many lifters in my boat during last year's boating season and then went researching the causes of those failures.

The question is - how is this affecting older Benz engines, such as in my 16v, 420SEL and 300SL?

Should I be switching to off-road only racing oil or Rotella-T as has been suggested by cam manufacturers for the solid lifter big blocks? Or should I be adding GM's break-in additive as has also been suggested by auto pros? Does MB have anything to say about the reduced ZDDP and the effects on their valve trains?

__________________
Thank You!
Fred
2009 ML350
2004 SL600
2004 SL500
1996 SL600
2002 SLK32
2005 CLK320 cabrio
2003 ML350
1997 C280 Sport

For sure you should be using API CI-4 HD diesel engine oil in any engine without a catalyst. Many vintage Mercedes owners have been using CI-4 in gasoline engines for a long time with no obviously apparent degradation of the catalyst.

CI-4 will be replaced by CJ-4 in about a year, and it looks like CJ-4 will have a limit on phosphorous content, which will limit ZDDP.

There's a recent article on the subject at:

www.LMTRUCK.com

Duke

Duke

Do you believe the CI-4 will be discontinued at some point? Should I buy a 55 gallon drum or two of the Rotella-T CI-4 oil? My 3 engines take about 4 gallons each. Or would you know if the oil manufacturers will still blend off-road only racing oils?

Or just bite the bullet and buy roller cams, meaning cams, lifter bore mods, lifters, different lengt pushrods, etc? Just doesn't make sense to me because I will be doing a top end rebuild every year on all three. I have no need to make any more power than I currently have available so I want to keep the exact cam profile I currently have.

I've read some of your engine related posts - I value your opinion!

__________________
Thank You!
Fred
2009 ML350
2004 SL600
2004 SL500
1996 SL600
2002 SLK32
2005 CLK320 cabrio
2003 ML350
1997 C280 Sport

I don't think there's any need to buy a lifetime supply of CI-4 oil. CJ-4 may not be quite as "good" (at least from my perspective) as CI-4, but maybe the phosphorous limitation is offset by the higher oxidation resistance. There are so many tradeoffs and so many different operating conditions, even the experts who deal with these issues everyday can't reach a consensus.

When CJ-4 hits the market I expect all the CI-4s to be discontinued. We'll have to wait and see. For sure CJ-4 will still be better for older spark ignition engines that don't have "roller everything" (like modern engines), than SM oil, and there are enough older diesels using high sulphur fuel, especially off-road, in operation that maybe some manufacturers will continue to offer CI-4 if the demand is there. I will use it as long as its conveniently available. Then I'll switch my cars to CJ-4.

CJ-4 may not be as good as CI-4 in diesels that use high suphur fuels, but that's not an issue in SI engines since gasolines are already very low sulphur, but I don't like the reduction in phosphorous, which will dictate less ZDDP, however less means there is less risk of SI catalyst damage.

It's all about many different tradeoffs and probably not worth losing any sleep over.

Duke

waybomb,

What a beautiful boat!!! The Videos show that, I like the start-up video, pure music!!!

I tend to agree about using Diesel Oils in your engines. I read Duke's post and the LMTruck.com article. It opens a lot of questions for the future.

I thought of this. Go to REDLINE or Mobil 1, if their specs fit your requirements. Call the Companies. Or go back in time, to the old Kendall GT-1 formulas, that Don Garlits and others used in their Dragsters. I used it for years in my engines that required it and it was loaded with anti-wear agents, the oil was a green solid color. 20/50wt, 50wt, Nitro 70wt.

The new Kendall Oil Co., doesn't make those oils any longer. What remained of the old refinery in Bradford, PA. does. This is the site for them, maybe they can help out with your situation;

http://www.amref.com/news/whatsnew.htm