Katalysts and DPFs

Hi Ranur,

The ACEA C specs are from 2004, so already quiet some time here. Please note that there are also some Mid/Low Saps specs which are related to the manufacturer, like:
MB229.31, MB229.51, MAN, etc.

The only thing which really can generate problems when using a Mid/Low Saps oil in a regular engine is the adjusted HTHS value of the C-oils. Some engine can have problems with these values.

Thanks!
I am aware of the low/mid SAPS manufacturer specs you mention.
The challenge is to understand if these oils can (or rather should) be used in models with DPFs and KATs prior to 2004.

There are not a lot of cars with DPF before 2004...

No, but a lot of KATs.

Mid/Low Saps are no real threat for normal oxidation catalysts.

Hi EM

I think I might have explained the problem poorly. I will try to elaborate.

There is no doubt that the catalyst or dpf last longer and function better with the low/mid SAPS lubricant in the engine. Residues from normal SAPS oil burning polutes the catalyst more than low SAPS oil burning.

The general issue here is that ACEA is putting up a warning sign in their description of catalyst compatible oils in the "ACEA oil sequences 2007". ACEA is of course not telling anybody exactly what application this warning is inteded for. They suggest us to check the owners manual if in doubt. No car prior to 2004 have any recomendation on using an ACEA Cx oil.

What about all the garages that put in Cx oil in cars produced prior to 2004 with catalysts. Is this engines compatible with the new Cx spec?

- Is it all engines with a sludge problem history? Is sludge problems increased with the low/mod SAPS?
- Is it the TDIs from VW?
- Is it the CDIs from MB prior to 2005?
- Is it the heavy duty low rpm diesels?
- etc etc.

In any case...how should the car industry understand ACEAs warning?

I have contacted some lubrication companies and similar to check out if this is a known issue in the personal car industry. So far they have not returned any good answers.

Ah okay.

Well, actually PSA (Peugeot & Citroen) are recommending C2 in retrospective back to MY 2000 for their cars, so their engines should work without any problems. I think we have to wait a bit longer for more clarity on this matter from ACEA and the OEM's.