Good oil article.

[Terry F.]

I thought I would share this article with people on the board and get some comments. Oppinions appreciated. I am a little confused and will have to read this article again but, it seems that the amount of ZDDP is dependent on the weight of the motor oil. EPA required that those motor oils that were used in automotive industy reduce it to lower emissions. I think we all know that. But, based on this article it sounds like wear protection packages are more related to oil viscosity range. Diesel engines tend to run the higher viscosity oils. Like I said I will have to re-read some of this. Maybe we should be buying BMW bike oil Read the article.

Take care, Terry

[Patrick H.]

What article? *NM*

[Terry F.]

Sorry about that

Little follow though problem there...here is the article. Terry

http://www.ibmwr.org/otech/oilreport.html

[Duke W.]

Re: Sorry about that

The amount of ZDDP is based on the API service category, not viscosity. This has been discussed numerous times on this forum, and I've made many detailed posts on the subject.

The bottom line is that the current SM spec has a limit on phosphorous, which limits the amount of ZDDP, and I do not recommend SM oil for vintage engines.

CI-4 oils have no such limitation, which is why I recommend CI-4 oils for vintage engines.

The only thing you need to know is what is the best API service category spec for your engine, and what is the proper viscosity range for the lowest consistent ambient cold start temperature you expect. It's that simple.

www.api.org

Duke

[John Chesher]

Re: Sorry about that

Duke,
Any harm in adding the 4oz. bottle of ZDDP additive from the Chevy dealer (I think it's called something like Cam & Lifter Assemble Lube" to every oil change, even though I'm using Rotella T? I used it, per your recommendation, during the break-in period and wondering if any harm or any benefit in continueing to use.

[Terry F.]

Re: Sorry about that

I will re-read that article I posted because I only skimmed through it. But it seems that the amount of phosphorus was targetted in motor oils within a certain viscosity range by the EPA because they were the most commonly used. I seem to recall that they talked about API ratings also and found several brands with the same API each having considerable differences in the amount of ZDDP. Those motor oils least effected seemed to be those not recommended by the auto industry. I appologize for any ignorance that I am showing on the subject. I became concerned a little because some of the diesel motor oils fall withing the catagory targeted by the EPA. I believe the article was also trying to determine if API rating somehow determined that an oil would have a certain amount of ZDDP. They showed that it varied considerably. But, like I said, I need to re-read and learn more about the subject.

Always appreciate your comments and opinions, Terry

[Duke W.]

Re: Sorry about that

Some additives like ZDDP can build up cylinder deposits, so it's good not to use "too much". The amount of ZDDP in CI-4 oil is more than enough to cover the requirements of a pampered spark ignition engine, and GM only recommends their EOS supplement for breakin, not after.

Duke

[Duke W.]

Re: Sorry about that

The article is okay, but somewhat dated - seven years old. What he speculated was a new "SK" became SL, and it was replaced by "SH" about year ago.

If you search this site on "SH", "ZDDP","CI-4", and "CJ-4" you should find current information.

Duke

[Terry F.]

Thanks, Terry *NM*