moribundman

The VW 505.01 spec Castrol oil didn't look special in the virgin oil analysis (See link). Whetever makes this oil special is a mystery. At least the price at the dealer has come down from $12 a quart.<ul><li><a href="http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=11;t=000157#000010. ">VOA</a></li></ul>

Hy Octane

use. They specifically require us to use this and no other, If you do use another brand and there is an engine problem, they will request an oil sample and if they see anything that they dont like as a result, they will void the engine warranty. Now I havent actually written to them and asked if I can use another brand, but with the price of these cars, and the fact that they supply the stuff for free for the first 50k, its not a big deal. It costs $16 per quart if you do want to change it more often than the 10k intervals Audi covers. I am going to pay for an oil change when I reach 10k sometime next week as I feel that 5k on an oil change is plenty adn 10k is too much. There are a bunch of PDF's about 505.01 if you do a Google search, but they are in foreign languages.. HTH.

moribundman

In the presence of other oil that meets the required spec, Audi will have to give you their oil for free per the Magnusson Act, if they insist that you use only their oil.

If an oil other than Castrol is VW 505.01 rated, you can use it without endangering your warranty. Motul sells one in the US. Others will probably become available soon.

I doubt the price is still $16 per quart. Last time I checked it was $12 and from what I hear it has since dropped to about $6 per quart -- which is still pretty high fr any hydrocracked mineral oil.

vBob

I searched around the net when my RS6 was due for oil change. I think one thing that I came across was sulfur content of the engine oil, and I think I saw it in one of those VW TDI forums. if you haven't gone there you might want to ask them.

I also dug out one (unsubstantiated) fact like 505.01 does not call for synthetic (506.01 does) which may explain why the Castrol VW505.01 and Motul 6100 VW505.01 are of semi-synth variety. (Bardahl XTC 5w-40 is available for those in NA seeking full-synth VW505.01-compliant oil.)

also VW506.01 (extended drain interval) can be used in place of VW505.01 oil. but VW506.01 is pretty much non-existant in the NA market.

if I can recall, the ash content of the oil somehow interacts with the gasoline (highish sulfur in USA) and does bad things to the emissions system.

moribundman

Most VW oil specs set a limit of 1.5%.

Hy Octane

I would like tp follow up on this info. I will contact AoA and let em chew on that. Thanx!

moribundman

Please let us know what they tell you.

vBob

okay, I was bit off. (: it's ash content and sulfur, eh?

http://forums.vwvortex.com/zerothread?id=1275763&amp;page=2

if you go down the page to a post by "Drivebiwire" he mentions an engine oil needs ash content of less than 1.5% AND 5w-40 to be VW505.01-compliant. fwiw, the Mobil-1 Delvac-1 (aka "SUV fomula") got 1.35% but from what I've read elsewhere the Delvac-1 is not advertised to be in compliance with VW505.01.

there are threads mentioning messing up the O2 sensor and/or EGR if wrong engine oil is used. but on the other hand, they're talking about TD engines. I wonder if that's applicable to gasoline engines?

interesting to note the Rotella T synthetic is only compliant with the VW505.00 and not VW505.01. I've checked with the local Wally Mart on that one.

moribundman

Thanks for the link. I checked it out.

The 1/5% sulafted ash limit is not unusual for any VW oil spec. The Euro Delvac 1 that meets VW 505.01 has a slighty lower ash content (1.2% vs 1.35%) and is little thinner than the US Delvac while the the flash point is notably higher.

If messimg up the O2 sensors is the main issue, then it's probably a combination of sulfated ash and the US fuel, which contains a lot of sulfur (ca 10x compared to Euro fuel).

if you go down the page to a post by "Drivebiwire" he mentions an engine oil needs ash content of less than 1.5% AND 5w-40 to be VW505.01-compliant. fwiw, the Mobil-1 Delvac-1 (aka "SUV fomula") got 1.35% but from what I've read elsewhere the Delvac-1 is not advertised to be in compliance with VW505.01.

I'm using M1 T&amp;SUV in my 12 valve motor, which requires VW 502.00 (actually the older VW 500.00, but let's not go there). I am doing that because Delvac/T&amp;SUV has the preferred viscosity, and because it's known to be Mobil's top synthetic oil. Seems to work well in my engine.

I'll keep digging for some more info on VW 505.01 and post my findings.