wrecks

I use the original Mobil 1 that is GM 4718M rated. I also have a BMW that requires Mobil 1 ESP formula. Does anyone know what the difference is between the two?

acrace

Looks like ESP has a slightly different formulation so that it is also compatible with diesel particulate filters. Can't find anything that tells me specifically what is changed.

Here's a link:
http://www.mobiloil.com/USA-English/...s/Mobil_1.aspx

If you look at the webpages for each specific formulation, you can also click on the "spec/approval" tab, if you're interested in that.

Also, looking at the tab for spec details shows a lower sulphated ash content for the ESP version, as well as a higher flash point. Perhaps the lower sulphated ash content helps with the emissions systems in diesels/European vehicles, but that's just conjecture by me.

LDB

Mobil 1 has a lot of confusing variants. Is your BMW a diesel? If not, it may be that they recommend Mobil 1 Extended Performance (sometimes called EP), rather than ESP, which stands for Emissions System Performance, mainly relating to diesel particulate filters. As far as I can tell, both EP and ESP are for long oil drain intervals, which means they would have more pH stabilizer and anti-oxidant additives. If you plan to run long oil change intervals like BMW recommends, that’s good, you need them. But if not, then you don’t need them. You might say why not go for it anyway, what can it hurt? But the thing about additives is that while they help in the areas for which they are designed, most are slightly poorer at the actual lubricating function. So if you don’t need the characteristic they are aimed at, why accept their slightly poorer lubrication?

If you really are talking about ESP, the only characteristic that seems to be much different for ESP versus the EP variant is that ESP claims low ash. Most of the ash usually comes from the additives, not the base oil, so it suggests that they have restricted use of higher ash additives. Now the question becomes, is that good or bad, and that’s a crap shoot. Maybe the higher ash additives were used because they were cheaper than other possible choices, and eliminating them would be good. But maybe the higher ash additives were there because they work better than the lower ash alternatives, and eliminating them would be bad. The web site doesn’t give enough info to tell that.

Bottom line, just be certain you understand with certainty which Mobil 1 variant is being recommended, and then use it. Don’t try to second guess about whether this or that characteristic would be better for your car, or for use in your Vette.