mithrilG60

Body roll can be reduced nominally via stiffer dampers, but not a huge amount. Sway bars will be much more effective for this.

Koni does makes a sport damper (ie. yellow) for use with the OEM non-sport springs, however you're right that they are typically used in conjunction with sport springs that will lower your ride height.

As for hitting the shock mount, the damper is bolted to the shock mount so it can't really "hit" it, whether the suspension goes fully unweighted or not. What SloopJohn is referring to is that stiffer dampers will put more stress on the shock mounts and dampers like the Koni or Bilstein HD can actually break through the OEM mounts if they're stressed enough. If you look at ETKA there are 2 separate rear mounts, the standard part used on all V6 cars without the sport suspension and an uprated part used on all V8 and armoured models. I believe he is recommending you switch t the uprated one when you replace the dampers to save yourself future hassles

mithrilG60

Body roll can be reduced nominally via stiffer dampers, but not a huge amount. Sway bars will be much more effective for this.

Koni does makes a sport damper (ie. yellow) for use with the OEM non-sport springs, however you're right that they are typically used in conjunction with sport springs that will lower your ride height.

As for hitting the shock mount, the damper is bolted to the shock mount and the shock mount to the shock tower so it can't really "hit" it whether the suspension goes fully unweighted or not. What SloopJohn is referring to is that stiffer dampers will put more stress on the shock mounts and dampers like the Koni or Bilstein HD can actually break through the OEM mounts if they're stressed enough. If you look at ETKA there are 2 separate rear mounts, the standard part used on all V6 cars without the sport suspension (including Avants) and an uprated part used on all V8 and armoured models. I believe he is recommending you switch to the uprated one when you replace the dampers to save yourself future hassles

m4dzl

What type and how much stress is necessary to break through the shock mount with the Bilstein HDs? This car is a seasonal winter vehicle for skiing and maybe light use through the year, possibly 5,000 miles per year . I am not going to auto cross it.
Are you suggesting that the stock strut/shock mounts cannot withstand the upgrade to Bilstein HD under normal low mileage use? or is the wear mileage dependent? or style of driving?

rocketman4321

If you select Bilsteins, note that there are errors in their online catalog for 2001. I think I now have the right ones, but AWE said they found a number of other errors as well. (Some of Bilstein's foreign sites appear to be correct.) I'll post an update to my earlier query as soon as I have a chance to organize and double-check the part numbers.

SloopJohnB@mac.com

My experience was that the stock 2K4.2A6 rear shock mounts failed with Koni yellow sport shocks at about 115K...10K after I put in the koni yellows.

YMMV.

SloopJohnB@mac.com

Only if you consider how bad the handling was with worn out shocks!!
The OEM shocks were soft from the beginning and at 105k they were soft enough to make you ill as well as learn to steer like a m-effer when going through a sweeper with washboard or oopsy daisy road swells. AFAIK the new Konis just damped the whoopty-does through the corners, better than stock. Of course, still have close to stock body roll which was ok.

The price for the OEM shocks was simply stunning at the time...stealer wanted $3K to do them, involved replacing entire strut/spring. I got the idea they didn't really want to do it.

I'm thinking even replacing the shocks with OEM components would have taken out the worn rear upper shock mounts.

YMMV.

MP4.2+6.0

since I also replaced all the upper and lower front arms, it hadn't been aligned in about 75K miles and it was eating up the inside front right tire (probably due to badly worn upper front control arms), I figured it was time. Sure enough, shop said it was way off, which I saw from the print out. Before and after was dramatic in terms of just kind of blah to really feeling nice and tight and like it wanted to go right down the road with a nice snug and determined feel. All the new parts helped, but alignment lent a lot more new car feel to it.

From having done the full changeout myself, I would say not required IF your alignment is good now, and depending on what you pull in the front. Rear seems very fixed already and that strut changeout was pretty quick. In the front, I think it depends on whether you pull out the upper mounting plate above the struts to which the upper control arms bolt, or you just pull the strut and spring unit only. If you do pull that upper plate too, that has some adjustment to it, at least on my 4.2, though you could mark its starting position. Some seem to do it that way, which surprised me a bit. I did it per how I read Bentley, which meant just leave that in place and unbolt two 13mm nuts that are accessed under some plastic body plugs near the top of the struts from under the hood. Those two nuts hold the shock and spring assembly to the upper plate on top. Not very hard. With that, nothing about the struts should affect the starting alignment. It does mean to get both upper control arms out you have to demo saw out one bolt on top given the dumb factory install, though you just reverse the new one and it slips in no problem. But again, not even applicable if you are just doing struts and not control arms.

Given what you do have to disassemble, it is a good time to do any brake work needed--pads, rotors, etc. The front roll bar U links are right there in the strut bolt up area too and, together with the upper control arms, have been the primary wear points I have seen over the years. Thus give your pads (rotors if need be) and those U links a look over before you finalize your parts buy. Very little extra labor if done at same time.

mithrilG60

SloopJohnB,

Did you change your springs at the same time as you put in the Koni's? Do you recall what level of dampening you set the Koni's at when you installed them?

m4dzl

Rocketman,
I have independently verified the part no. for the HD Bilsteins for my 2001 Avant Quattro 2.8 through Bilstein's website, Tirerack, and another vendor. But the latter two may on Bilstein's website.

What are the correct part numbers?

m4dzl

Here are the part nos from TireRack's website which are consistent with Bilstein's website for a 2001 Avant A6 2.8

Housing: Shock Housing
Non Adjustable
Note: Front fitment. Heavy duty.
Manufacturer Part #: 24-020794


Rear Fitment
Housing: Shock Housing
Non Adjustable
Note: Rear fitment. Heavy duty. Excludes V8 models. For models from 05/00-02/05.
Manufacturer Part #: 24-065092