DRC vs Bilstein/Koni Struts.

[GBG]

I do quite a bit of suspension modifications and repairs on Audis. The A6 4.2 weighs around the same as the RS6 . The struts for an A6 will definately work on a RS6, no question. So will A6 4.2 H&R or Eibach springs for the 4.2... All that, with the sway bars can be obtained for under 1200, and I can install it for 600 plus an alignment... Don't be fooled into paying more for an RS6 specific suspension, because it's baloney... Other than the DRC, this suspension is the same as the A6. If you buy adjustable struts or coil overs, you will always think you could have adjusted them better... I like the fixed style, simple, and nothing to worry about, and totally reliable..

Due to the cars lower height, you must use the Bilstein Sport Strut, because the rod is shorter and will not bottom out with the RS6 lower ride height.

I spoke to the head tech at my dealership yesterday about the DRC. He said that the ride height should not be affected by the DRC pressure. I know that counters what I've read on this forum, but that's what the techs are taught anyway. If the car sits higher after the recall, it's probably due to the position the control arms were in when the were re-torqued. The car sits on the springs, not the shocks..He said that clunking indicates that not enough fluid was injected into the sytem on install.Not so much a pressure issue.. Either way, it seems to me this is a problem that will never go away, and I hate the fact I lack the tools to fix it myself, as that is the only way in my mind the DRC will ever work correctly. I cannot tolerate a rattly clunking car.. And I cannot bring myself to pay the dealer to do what I do all day long...

My DRC replacement strategy is go cheap, yet sufficient. All you really need to do, is replace the struts and sway bars, as long as you are happy with the ride height, as is stock.. Some Bilsteins have grooves cut in them, so you can lower the spring perch, thus lowering the car. If the back sits too low, you can also raise it up if need be..

I want my car to handle crisp, but lets face it, this car is not a race car. It is big and heavy, and will never handle like a RS4 or M3. Sure, you can kill the ride quality and make it ride like a hay wagon, deriving slightly more responsiveness and lateral traction in the process, but IMHO, not enough to make it worth while. The car is not balanced, and that is very hard to overcome..

I'm gonna give the dealer one shot to fix it right, but if they BS me, or try to charge me, I'm going to do what I proposed above.

Innovator,

Thanks for the informative post. What set up would you recommend if the goal is to (1) drop car to lower ride height and (2) stiffen ride so less bounce, less body roll? Thanks GBG

[Innovator]

Innovator,

Thanks for the informative post. What set up would you recommend if the goal is to (1) drop car to lower ride height and (2) stiffen ride so less bounce, less body roll? Thanks GBG

Tirerack.com

H&R springs and Koni adjustable sport struts.. or

Product Details
The performance characteristics of this product place it in both Premium and Performance Street categories.
	Front and Rear Fitment Ride Height: Threaded Adjustment Note: Avg Low 1.5-2.5"F 1.25-1.8"R		Price: $1,248.00 (kit) Estimated Availability: 12/11/09 Manufacturer Part #: 29482.2

[GBG]

Tirerack.com

H&R springs and Koni adjustable sport struts.. or

Product Details
The performance characteristics of this product place it in both Premium and Performance Street categories.
	Front and Rear Fitment Ride Height: Threaded Adjustment Note: Avg Low 1.5-2.5"F 1.25-1.8"R		Price: $1,248.00 (kit) Estimated Availability: 12/11/09 Manufacturer Part #: 29482.2

Thanks very much for the recommendation. GBG

[micdee]

Well I found this thread a little later after I already posted my questions.

But as my questions fit better into this thread I will add my questions here again and we can continue in this thread.

Ladies and Gents,

I have been member of this forum for some years as I owned a S6 (build 1999) for a couple of years and recently bought myself a RS6 (2003)
I live in the Netherlands, that is Europe. (so excuse me for my language ;-) )
Now I found out that my DRC is not what it supposed to be.
So I am in the decision period what to do: repair of the DRC or replacing the entire DRC for shocks and springs.

I did try a search action on DRC and replacement but thus far all I read is that the DRC kind of uhmmm is of poor quality and needed to be repaired.
Also that some of you replaced the DRC with a complete set: KW set (variant 3) and also H&R, but with the latter I think to remember they used H&R springs to replace the OEM springs.

So I'm calling in your help about which mileage or km's you made with the new DRC struts installed before you needed to replace them again.

What mileage did you do with the after market shocks and springs like the KW v3.

Does the "rideability" of the RS6 change completely with the after market set.

And when I decide to do the repair is it better to renew all 4 of the struts at the same time?
I know the right rear is leaking som oil (according to the Audi engineer the leakage was not a problem. Uh huh?!?! Now I know better)
May be a better question is what should I have repaired of the DRC? (I do not know if there was some sort of recall action by Audi in Europe and if this Audi has been back for it; it is not in that "service-thing" I got with the RS6)
Thank you for any help as I could not find any on the Duth fora/forums/forea?!?!

The answers I already got I will quote in here as well:

This is just my personal opinion and experience, but I would just remove your DRC system and go the coil over route. I have the KW V3's and have done about 35k miles on them with no problems. The Kw's right out of the box offer a comparable ride to the DRC, but I have mine set a little firmer. If I were you, I would look into the H&R coil over setup, as it should be available to you over in Europe (we can't get them here for the RS6). The H&R's are much cheaper than the KW's, and I've read that the ride is more compliant.

Also, I said it in that thread, and I'll say it again, I don't like the idea of installing a Koni shock and H&R spring combo on an RS6. That setup is not DOT or TUV approved for the car, and I would assume you have yearly inspections over there. I don't think it will pass with that set up.

Micdee, I would check with the dealer to see if your car has had recent DRC work done, how many miles on the car? There was a complete DRC recall in North America but I'm not sure about Europe? Maybe another European member could chime in. Since Netherlands is part of the European Union I would think Audi would have to treat all members the same if there is a recall going on over there.
As for aftermarket solutions, known ones are KW V3's, H&R, Bilsteing, and Ohlins. I can recommend the KW's as that is the route I went with and I haven't heard of any complaints about the KW's or the H&R's. I have heard good & bad about the Bilstein & the Ohlins. H&R also offer a spring replacement for the stock factory DRC springs which lower the car a little (2c.m.) and increase the spring rate slightly. These springs go over the stock DRC so you may still end up with DRC problems.
Overall, a working DRC is a good driving system with little compromise in ride & handling. I didn't like it mainly for reliability and the ride height. A good aftermarket suspension that is fully adjustable can do better on the track but then it will be much more harsh on the street, you can soften it up a little for better (not as quite as good as a good DRC) street ride while still being good in the performance role. My KW's make the car handle better than the DRC was but are a little harsher on rough roads, most of my roads are pretty good around here but if they weren't I may have stayed with the DRC and worked with the dealer to get the ride height better, at least while it was still on warranty. Let us know what you find out and decide, I'm sure some other members will chime in too. Welcome to the list.

[micdee]

Tomorrow I will go to an Audi Dealer nearby and I hope we'll might be able to check if the replacement has been done already.
All I know is that the DRC has been refilled (as the seller told me)
But when the recall has not been done yet, and there has been a recall for this in Europe, I do not think Audi will be very keen to do this on my car now.

So what I still would like to know is what mileage of km's owners have done with the replaced /repaired DRC?

When you replace the DRC (completely) do you need to do more then only the absorbers with springs.

And at this moment I am not looking for lowering the rideheight. I need to go over 10 speedbumps to get out of my neighbourhood and some are a real pain in the ......
before the RS6 I had a Golf IV R32 and with that car I hit the exhaust at some of thise bumps even with a speed of 3mph. With the RS6 I have had no hits yet.

[hahnmgh63]

This won't really answer your question but I replace my DRC with KW's at about 90K Kilometers. My DRC was still working (I seemed to be only 1 of a couple that had working DRC at this mileage without a trip to the dealer or three...four...) but a slight seep was showing on the front struts. I did the recall first and the car was little firmer but sat too high in the rear. I did a return trip to the dealer which lowered the rear a little but still too high for me. As I mentioned, the dealership is about a 3hr round trip for me and I was fed up with it so I installed the KW's and have been smiling every since. My car now sits about 1.5" lower than originally but I too travel or a couple of speedbumps and nothing rubs at this height but I think the car looks better and handles better than ever before. The nice thing about the adjustability is after originally lowering it 2" I decided to raise it slightly and it was no problem. As Innovator said the RS6 is no race car for sure but between the KW's and a good alignment with ride height & weight balance (can't be done on a DRC or non adjustable suspension car) and a few selected mods: Lightweight battery (saves 16+ Kilos), lightweight forged BBS wheels, etc..., the car handle pretty dam good and you can see a few RS6's on Youtube tracking and blowing M3's off the road.

[micdee]

@ hahnmgh63 : thank you for your insight. Hopefully others can tell me their experience.

Perhaps you can tell me this: do I need to replace more then only the struts and springs?

[hahnmgh63]

I did replace the upper strut mounts while I was at it as Audi didn't replace those during the recall. The front and rear upper strut/shock mounts are fairly cheap. About 6 months later I replaced my upper & lower control arms as they were quite worn, especially the top inner control arm bushings, they were shot. All C5 A6's seem to wear out the bushing fairly quick 60~90,000 Kilometers.

[micdee]

Well it seems there has not been a recall in Europe, or at least not in the Netherlands.
After a phonecall with an Audi specialist and my visit to the Audi dealer I decided to go for a renewal of the DRC.

I kind of want to keep the RS6 as near to the Audi concept as possible. So all I hope is that the repaired DRC will hold for a couple or more years.
I will have a 2 yr warranty on the repair. And I go for a 4 struts renewal.

[hahnmgh63]

That is all the North American recall replaced, the two front struts and the two rear shocks. The original springs, central valves, and the upper strut/shock mounts were all re-used. Some expensive work and cost for all, and it needs to be done right which was also part of the problem here. Most dealers didn't get it right the first or second time as the cars didn't sit right or the pressure was wrong, all because of improper training. Many cars had their suspensions tightened down as they were lifted in the air? Any good mechanic knows that a suspension with rubber bushings needs to have the car weighted before you tourqe the suspension down, the factory shop manual even mentions this but many shops here didn't do it. The recall here only gives a one year warranty so if your getting two years that is a little better. Good luck with it if you do choose to go this route.

[micdee]

I hoped to have some more reactions, but as I did not like the situation with the suspension I made the decision to go for the DRC repair/renewal.

They say, they have done some more repairs (on a couple of RS4's), so hopefully they do know what they have to do.
There are a few things I will mention before they start: same rideheight as it is now and to replace the upper strut mounts.

I will keep you informed. Repair is in three weeks.

Tnx for the effort. I know what I will do when the renewal will proof to be a mistake of me.

[micdee]

Guess what, after I made the appointment to repair the DRC I still kept on reading about the DRC and the problems.
I start doubting more and more. So I called the shop that sells the KW 3V sets and they told me every V3 set is hand made and will go for about 100k km and they will fit it for the same price as the repair for the DRC so.........................

Yes I changed my mind. I will call Audi on monday to cancel the appointment and when that is done, I'll make the appointment for the KW V3 set and hopefully we can do the strut mounts and H&R stabilizer at the same time.....

I hope Audi have not yet ordered the struts......

[hahnmgh63]

KW's lifetime warranty and a little Google searching looking for feedback from others was a definite selling point for me + the height adjustability. It beats Audi's 12mo/12,000mi warranty anyday. How many of our N.A. listers that had the recall done ended up happy, and that is just the initial with the ride height? Many had to make multiple trips to the dealer to get it solved, some never had it solved. And how many have already had problems, not a lot but it has only been about a year for most.

[Aronis]

Innovator,

When my DRC went four years ago (the first reported failure on the East Coast), I asked if the regular shocks from the A6 would fit and they said yes, But would only change over if I paid 100% of the cost! And as the car was still a lease car, said I would have to pay to put it all back to DRC before turning in the car! I was close to doing that change over until I stumbled on a better dealership with a better RS6 mechanic.

Mike

[SteveKen]

Innovator,

When my DRC went four years ago (the first reported failure on the East Coast), I asked if the regular shocks from the A6 would fit and they said yes,...

Can you post or pm me any other details on this? I'm extremely curious and have a set of S6 and A6 suspensions lying around. Even though I'm not fond of it, I've been known to do some trial and error, so . . .

[ttboost]

Does anyone know the weight savings in removing the DRC and installing coilovers, if any?

[hahnmgh63]

I posted the weight difference when I did mine a year and a half ago. I don't recall exactly what it was but I want to say it was at least 20~30lbs, maybe more. Should be somewhere in the archives. I'll see if I can search my own posts? I removed the shocks/struts, central valves, and all of the hydraulic lines.

[ttboost]

Do you remember how long it took? Are all the ancilliary parts located in the stock shock locations? Or are there parts hidden all over and under the car?