RajDatta

Because they are probably completely uncompressed due to their higher effective rate.

tamathumper

The spring rate of a shock is zero, AFAIK, and they don't change effective rate as I understand it. They only dampen movement, and once on the car, they are as compressed as they're going to get, unless they are too long for the application in which case they're bottomed out.

https://rennlist.com/forums/5946855-post6.html

Jacks911

These are direct replacement Bilsteins Shocks for the rear - not coil over units. The raised ride height is most likely from the gas pressure in these shocks bring greater than the 19 year old units they replaced. I had the same thing happen when I installed Bilsteins all around on my A6. The car was definitely higher... and still is - kinda SUV like - but it is our Snow in the mountains car so it is OK. By the way the Bilsteins Sport Shock on the Audi work great and ride very nicely. Despite the ride height the car handles better than new.

Can anyone tell me me more about the Brey Krause Underbody brace?

mbardeen

I think I'd get that rear ride height fixed before starting to throw more money at parts. Your increasing cowl shake might be because of more weight being loaded on the front, rather than being evenly distributed over the entire suspension.

Jacks911

The Cowl Shake was there before the rear Shock install and has not change after. Two different Mechanics suggested the shocks could be the problem so that was why I replaced the rears as that was an easy fix. Again it did improve the ride and limited Squat on acceleration and cornering is better in sharp turns... so it was worth it.

Other than trying the suggestion to install a Design 1 Racing Lower Suspension Castor Brace - I think my next effort will be new OEM Struts. and a full alignment.

mbardeen

In my experience, when troubleshooting a problem you really only want to change one thing at a time to control variables. You've changed the shocks but that also changed the rear ride height. You've changed two things there, so you still can't completely eliminate that as the problem until you've reset the ride height back to what it should be.

That said... if you're looking for an excuse to change the struts, go for it. With 20 years on them, they're probably due for a change. A full alignment and a corner balance can't hurt either.