MP4.2+6.0

Summary:

8D0 407 515C, used with PR1BK and PR2MA, which should be A8 std. and A8 sport

4E0 407 515D, used with PR2MB, which should be S8.

Background and Details:

I decided to poke at the subject of the upper control arm bushings further. As we know, one of the weakest (literally) links wear wise in the whole D3, if not the worst. There was a post on the subject of control arms a few months ago, here: Labor cost of to REPLACE FRONT UPPER CONTROL ARMS - AudiWorld Forums

I went back to the Audi Euro EKTA parts slides to look at the fitments, figuring on next brake job or winter wheel switch I am going to give the current ones another very close inspection for current condition.

It distills down to there appear to be two different sets of upper arm part numbers (each side, front and rear), and two bushing part numbers. The inner bushings are the same on all possible upper ams covering both sides, front and rear. That is, qty. 4 of the given bushing part #. Basically if you have either the base suspension or the A8 sport suspension you are in one set, while if you have the S8 you are in the other. It also turns out when you look at the European models and find the "armoured" (as in, heavy...) variant, it also uses the S8 arms by part number. They don't actually show the bushing for that set of arms as a separate piece part, but the arm part numbers tie off.

I also poked further at some of the slides you can see a lot more easily on the Euro EKTA, and basically found the A8 bushing used on about a gazillion models of A4's and A6's. If you type it into audiusaparts.com, you get literally 548 hits; its a $25 discounted price dealer part for bushing only: Audi Parts - Audi Wholesale OEM Parts | Audi Genuine Accessories | Audi Branded Collection | Audi USA Parts Online Catalog estore

When I looked carefully at the RS4 and the second gen RS6 (Euro only), sure enough it was the S8 bushing. On the audiusaparts.com web site you get 82 hits, including the S8 as expected, plus the V10 (C6) S6, and also the V8 S4's and RS4's. Out of left field, it also listed the BVJ 4.2 A8 motors--the later FSI ones. Priced at $39+ Audi Parts - Audi Wholesale OEM Parts | Audi Genuine Accessories | Audi Branded Collection | Audi USA Parts Online Catalog estore Euro EKTA didn's show any change based on the BVJ motor or with the 2008 facelift, or even all the way to the end off the builds in 2010.

More specifically I found this:

8D0 407 515C, used with PR1BK and PR2MA, which should be A8 std. and A8 sport

4E0 407 515D, used with PR2MB, which should be S8.

In the arms, skipping all the main part numbers, if it ended with an E it was for the A8 versions and aligned to the A8 bushing number by option code, and if it ended with an F, it was the S8/PR2MB code. During the search, I noticed what seemed like a variety of predecessors codes with earlier letters.

Also notice the S8 bushing has what I think of as a "true" D3 part number that starts "4E0" (as does the RS4 and RS6 listing). The 8D0 is one I think of as very generic or with A4 type origins.

My net for my own D3 W12 conclusions is given I also tied the part number to the "armoured"--which is a W12 based limo type D3 with another 700 pounds of ballistic stuff, pyro doors and fire suppression gadgetry, when the time comes I will be headed the S8 4E0 direction. The "armoured" spec also uses the W12/S8 385mm brakes in front, also more weight than the A8 360's. Said another way, the "armoured" application (via the arm part number match up) is also messaging to me that is the heavy duty spec.
Two more scary oh by the way thoughts:

This site tied to the 8D0 part number with the Meyle logo and the slogan "Connecting Buyers Width China Suppliers" did not warm my heart, and is reinforcing my suspicions and experience with Meyle sourcing from China, which I don't connect with quality. 8D0407515C,AUDI (FAW) 8D0 407 515 C Bush, control arm mounting for AUDI,AUDI (FAW),SEAT,VW My experience as well is as soon as the part connects to an A4, or actually especially an A6, the risks of Chinese sourcing instead of Euro sourcing on Audi aftermarket have gone way up in recent years.

Then there was this site, also including the 8D0 part number (and a bunch of other similar looking bushings): Brand New Engine Mount For AUDI 4F0407183A/ 8D0407515B/ 4E0407181B/ 8D0407515C/ 4D0407182E/ 4D0407181H, OEM Number 4F0407183A/ 8D0407515B/ 4E0407181B/ 8D0407515C/ 4D0407182E/ 4D0407181H - Chongqing Wholesea Commercial Co., Ltd Shows direct Chinese supply of the 8D0 number, and that it is shipped to both North America and Europe. BTW, they refer to it as an "engine mount"...

Thus, note to self for the umpteenth time on these: buy only from dealer, or look again at arms in my W12 to confirm they have Lemfoerder manufacturing stamping (not sure on uppers, I think I remember it on lower), and then have that brand as fallback plan B or price comparo. But, it probably takes me right back to dealer since I found sites like even Rock Auto showed the Lemfoerder part number (2931801) cross referenced to both Audi bushing part numbers. Not comforting either.

Hope the info helps, and any additive Audi D3 OE bushing data welcome. As I think others have found, I never uncovered any information describing at a spec or materials level the actual differences in the two bushings by part number. You can find images of either if you search via Google Images, but given the Lemfoerder parts crossover/single number, I didn't have much comfort any non-Audi parts pictures were correct.

NightOwl

Interesting finds MP4.2+6.0!

About two minutes before I saw your post, I was thinking what are the difference suspension wise between A8 standard suspension, A8 sport suspension and S8.

I'll keep this in mind when I need to replace those on my car.

MP4.2+6.0

Later/searching edit: these bushings all the way through to the ones used on the D4 A8 and the current A4/A5/Q5 type bodies--in a variety of yet different numbers, and on the D4 changing at least three times already--all come up with an OD around 47mm, an ID that is consistently 10mm, and a thickness of just about 40mm. But, the data comes from China aftermarket sites supposedly spec'ing other suppliers' bushings, the data is incomplete, and the data on OD often varies several tenths of a mm across supposed suppliers even for the same audi part #. Some of the width data gives two numbers, but it may be measuring both the outer metal bushing and the inner through bolt shaft area. Overall, that data doesn't seem reliable enough, other than to conclude these bushings have stayed quite similar for many years now, the center bolting is the same diameter wise, and there are a bunch of small part # differences even by Audi.

mishar

I did similar research this spring when I replaced bushings for the second time in four years. My conclusion was that there is no firm conclusion. Different catalogs are sowing different numbers, enough to become suspicious if they know what they are talking about. Adding production origin (not necessarily good or bad, European or not) and recently D4 problems, tells me that we are doomed to replace those bushings every now and than. Guys also tried polyurethane bushings just to find that they are terribly noisy and don't last long.

All that didn't help me at all so I just decided to try S8 bushings. First I must say that I can't see any difference between the two, except price. Of course that rubber might be different, probably harder on S8's. If that is the case it may be actually worst when used on A8 with a bit longer height adjustment.

Another homework question: What about Bentley Continental bushings? Do they last longer on an even heavier vehicle, are they of a same size as ours, where they can be sourced and what is the price?

mishar

Pardon my "professional" drawing. I was lazy to crank AutoCAD.

MP4.2+6.0

Continental: in its own part numbering scheme, but here is a page on it: Wishbone, Upper & Lower My prior experience looking at Continental stuff is, as expected, it tends to be either direct Audi underneath, or gussied up if it is a trim part. Similar conceptually for Lambo Gallardo to R8, if dimensionally the Audi part is the same.

Similar idea: Phaeton. Once you said Continental, it dawned on me to check the similar steel porker VW Phaeton W12, plus it still soldiers on in Europe while the D3 got superseded. I can pull those off the same Euro EKTA site as Audi parts. I got: 8D0407515C . That puts me right back at the A8 std. and A8 sport bushing by part number. Likewise the whole upper arm component always came back with the "E" part number version. Also suggests to me that at least in Phaeton world these bushings aren't used for finesse handling or weight related tuning, both since that body (like the Continental) is the much heavier steel one, and on the Phaeton in Europe it is everything from 6 banger to W12, and both FWD and Synchro/quattro. Every slide I checked for every year had the same part # with no differentiation by motor. If anything, I might have expected the other 4E0 S8 type part number, at least on some, since the A8 Armoured with the W12 probably still weighs in somewhere around the heavier Phaetons (or the Continental).

MP4.2+6.0

If you play with this China site and put in different Audi OE part numbers, some of the dimensions come up here and there for various suppliers, plus some supposed pictures.

4E0 407 515D_For a variety of brands of auto parts[Quote Parameter Picture] - YiParts

EHLO

Thanks guys, I'm assuming the choice of VAG specifying the S8 or the non S8 one on a particular model is just for firmness of control, and not wear resistance.

MP4.2+6.0

Read the long original text, and note the reference to the "armoured" D3. Logically that application is about weight and heft, since it is basically the limo for heads of state, corporate execs, supposed stars, and hanger's on for all of the foregoing.

That one is going to be tuned logically for the 700 pounds of added weight, but they are presumably going to go for limo ride, not the most aggressive (for a D3) sport tuning like the S8. Owning the W12 on which the armoured is based, it's already a bit of a mishmash in other parts of the suspension--the comfort level air units, mixed with the A8 sport level of roll bars (but still one short of S8 bars).

To the heavier duty idea, here is a paste from the Jim Ellis site--which uses basically "true" US Audi EKTA parts listings and material instead of a copycat like the other online dealers do for cost/licensing reasons. It's for the A6 application of the 4E0 S8 part number. Notice references to rough road suspension options here and there, surrounded by references to both standard and sport set ups:

tx170754

I've had the W12 Phaeton, the A8 and now he S8. Both the Phaeton and the S8 did not have any creaking problem, the PO of the A8 ( California car) did change all the control arms at the dealer just before selling the car, however, once the winter came I started to hear the noise right away....