RI A6

<center><img src="http://www.teraspeed.com/RS4/oil%20sample%203134%20miles.jpg"></center><p>For those interested, here's a used oil analysis (UOA) after changing the factory oil to Elf Excellium LDX 5W-40. After the change I put 1300 miles on the oil before this sample, mostly on a 1200 mile highway trip, with about 3 hours of stop and go, a few 120 mph run ups, and about 200 miles of fun twisty, turny West Virginia mountain roads. Average mileage for the trip was 20+ mpg.

There are several things to note.

Originally I had been led to believe that factory oil was replaced at PDI with Castrol Syntec 5W-40. However, I've now learned this is not the case. At this time, the factory oil type is a mystery.

Oil consumption has dropped to near zero.

The Elf oil holds up pretty well and doesn't shear down as severely as the factory oil. (Which is why I recommend early change out of the factory oil.) This can be seen in the viscosity numbers. (100C 9.3 to 12.4 is the 30W range. Factory oil has sheared almost to a 25W oil, whereas Elf is at the top of the 30W range.)

There's still quite a bit of fuel dilution, as seen by the oil flashpoint reduction of 420F to 320F, but the Elf oil is standing up to it. Fuel dilution may be a characteristic of this engine, due to the low tension rings. Only time will tell.

Rings and cylinder walls are wearing in well, as indicated by the reduction of Aluminium, Silicon, Tin, Chromium and Molybdenum numbers.

Bearing wear is coming down, as indicated by the lower Copper number this time.

Valve and cam chain are still at nearly the same wear rate, as indicated by the Iron numbers. This area of the engine may take the longest time to wear-in.

For those interested, I used an aggressive break-in regime. Engine was broken in after oil reached operating temperature (200F), with 3/4 throttle acceleration in 2nd gear, within Audi engine rpm guidelines (6000 rpm until 600 miles, 7000 rpm until 1200 miles, 8250 rpm briefly until 1500) , followed by compression deceleration, with cool down periods, and repetition in 3rd gear. Remainder of driving mixed 40%/60% local/highway driving.

AUDIFAN008

good stuff =) how much oil sample is needed to do a test?

RI A6

4 Oz. If you go to http://www.dysonanalysis.com/, you get the sample bottle with their Premium analysis kit.

Here are some ways to take samples.
http://www.cartermachinery.com/products/sossmpl.pdf
http://www.amsoil.com/storefront/oai.aspx
http://www.blackstone-labs.com/pump.html

I've tried both Blackstone and Dyson for analysis. Dyson is more thorough and has better accuracy. Also a bit more expensive. ($40 vs. $20) Blackstone also has an option to have Terry Dyson provide a reading of the report. I've found him to be extremely insightful.

wagongotya

<ul><li><a href="http://www.blackstone-labs.com/">http://www.blackstone-labs.com/</a></li></ul>

crew219

That ELF didn't work out as well as it should have with only 1300miles.

Dave

RI A6

But it is much less than the factory oil. Which daveak05 took offense to when I called it "swill" writing:

"Oh, that factory swill is probably the best oil that will ever be in your car ...."

Well, we've now proved that wrong. That factory oil sheared down to a 25W. Elf, on the other hand, sheared down to the top of the 30W range.

Blackstone labs seems to think that this engine will shear pretty much any oil that we put in it. Terry Dyson thinks that we can do better, but that the Audi 502 spec is getting in our way.

Next stop ... Motul E-tech

crew219

I've seen UOAs of the stuff and I haven't been impressed.

Ever think about throwing in some more viscous stuff (50wt) for the initial break-in period until your wear metals stabilize?

Dave

RI A6

The reason for Motul E-tech is it's ability to mix well with the various 300V ester oils with similar chemistries.

Bob W.

you can't because you don't know.

so what are you going to do now, change the oil every week?

daveak05

I wouldn't say I took offense to that. It was also in the context of the oils being mentioned, such as: Mobil 1, Valvoline, US Castrol. I still find it hard to believe that Audi fills the RS4's with a weak oil. Maybe all that fuel dilution had something to do with a bunch of cold starts and moving the thing around lots in Germany and here.

Bob seems to think you'll on overkill here, and I tend to agree a little with that. Not that what you're doing isn't sound stuff and good to know, but there is so much more to the car than than slight variations in oil, brand to brand.

I was also surprised to see such high concentrations of magnesium, zinc, and phosphorous in the ELF. The zinc and phosporous are not good things in higher %'s, from what I recall in oil research.