[nickm]

The big deal about 505 and 507 is specific protection for cam lobe wear. 507 is for dpf and 505 is non dpf. The way the tdi engine is designed, it requires a specific oil to prevent premature cam lobe wear.

Any modern diesel oil can deal with dpfs, but only 507 can deal with cam lobe wear prevention.

 

[nickm]

It baffles me why anyone would buy a $50K+ premium precision vehicle like the Touareg and then fret over an extra few dollars for an oil change.

Il be honest with you the LL03 at my dealer costs less than any other synthetic brand I can buy at whatever store. 7 bucks a litre is pretty much the going rate for any synthetic oil

 

[nickm]

Cam lobe wear is ONLY a critical issue on pump-deuse injector motors. Anything with a common-rail hpfp and piezoelectric injectors does NOT have the extra cam which takes up space and makes all the cams the limiting factor.

To the op - all the diesel manufacturers qualify the engines/emissions control systems as a unit. The proper additive package in the oil is just as important to correct emissions control function as the O2 sensors are. The additives (think zinc which USED to be a common anti wear additive) CANNOT be allowed to contaminate catalytic surfaces. If that happens the emissions systems fail. Hence, many manufacturers are pretty insistent that ONLY listed lube oils be used. Also, manufacturers are required by US law to make sure alternate sources of maintenance consumables are always available WITHOUT having to purchase from the dealer.

There is a long list of 507 oils that you can buy Anywhere so nobody is saying you must buy it at the dealer.

Every current diesel sold on this continent has cats, dpfs and urea injection, so there is nothing special about VW spec in this regard that every other diesel oil spec doesn't already meet, so none of those reasons are why 507 is special.

Afaik the relatively narrow lobes of the camshaft was the reason why cam lobe wear was a big deal.

 

[nickm]

In the CR TDIs I don't think cam wear will be an issue since they have roller rockers now.


-J

When did VW ever use flat tappets? Afaik all tdis have been roller rockers

 

[nickm]

Just on the consistency theme, I'm beginning to wonder if that's why VW mandates the 507 spec. They know what 507 is all about and in the case of a warranty claim there becomes less doubt on if the proper oil was used. There are some very low quality oils out there, so I suppose it's much easier to not fill a warranty claim based on improper oil grade as the requirement is set up front.

GM is starting to do something similar with the higher end 6.0, 6.2 and 7.0 engines, where the "factory filled with Mobil 1" sticker under the hood is a strong suggestion to use a single specific oil.

When my Ford 6.4 diesel barfed out a piston they not only checked for oil change interval, but also which specific oil I had used.