Additive clash

[JHZR2]

Hi,

I am curious about additive clash. DOepending upon the weather, my past and anticipated driving habits, and what oil type I want to choose this time, I tend to swap oils a lot. I have read a lot of posts talking about additive clash from using different brands/types of oils.
I would like to know more about additive clash. Especially regarding its potential effects.

Example: My 83 MB 300D turbodiesel...
Change the dino oil every 3k miles in the summer. One time, Rotella, the next, Delvac 1300S, the next Delo 400. I realize that the oil cooler holds almost a quart, and the internals all have oil in them, so I end up probably having 1/8qts of oil being old, used, and a different brand stuff.

How much of a problem does this pose? The fact that there is this much oil in the engine is not something I can do anything about. It is designed this way, and Im not going to remove my oil cooler. However, does the use of different brands pose a problem? I am sure the additive levels are so high that they ought not be used up by 3000 miles, but still, if theyre clashing, I am not happy.

Any info on this is appreciated.
Thanks very much,

JMH

 

[sprintman]

Why 3 different brands? curious.

 

[JHZR2]

those are the three top diesel oils sold at wal mart...

 

[Bio-T]

All 3 are good oils and your engine will survive. Personally I would stick with the Delvac 1300S and is generally cheaper at Wally World. Or next choice would be Delo 400 which is always in stock. My last choice would be Shell of the three. Just my own preferences for OTC dino diesel oils. I would also look at the Pennzoil 15W40 available at the same store. Even though owned by Shell, Pennzoil had their own formulation long before the merger and I would use it with no problem.

[ February 04, 2003, 12:42 AM: Message edited by: 59 Vetteman ]

 

[Patman]

If you're always changing every 3k, additive clash isn't much of an issue. Additive clash will mostly affect how the oil oxidizes in the long run, and it's TBN retention. So it's something to be concerned about only if you're doing extended intervals. If changing before 5k, this additive clash should not pose any serious risks.

 

[Pablo]

I agree, at 3K OCI additive clash is not an issue.

Your car IS a diesel. Why not settle on a good oil, and with analysis - extend your OCI?

 

[widman]

While additive clash should not be the real problem, I would stick with one brand to get the full benefits of their package. My choice is Delo........
Additive clash is really when you mix oils of different pH and add humidity/water. You don't want to mix a motor oil (alcaline) with a transmission oil (acidic). In industry where there are hundreds of different oils I see a lot of stupid mixtures that produce horrific results.

 

[Steve S]

additive clash is a bunch of baloney if you look at the specs on the oil there may be a mil. spec. number. This is a spec. that means that a product meets the spec. the military buys stuff from the lowest bidder so for example Chevron oil one year Shell next year etc. etc.. The oil sales and marketing use addive clash to get the"stupid" consumers to stick with their brand of oil and it must work . But there is a but certain lubricants do not mix as widman posted . I know PAG an ester turns petrolium into jell like globs. I would mix any like oils and would be totally safe .