I put FSD’s on my 2005 Cabrio S 10 years and 58K miles ago. I've now got just 70K miles on the car. Also have a 19mm sway bar and non run-flat tires. The FSD made a huge difference originally but lately the ride has deteriorated. The rear seems particularly harsh over bad pavement. Seems like the FSD’s might be shot. But on the other hand I’ve never changed front or rear control arm bushings.
Wondering how many miles others have gotten out of their FSD's...

 

3 years and 7 months and around 55K miles, many of which are extended road trips and they're still going strong.
You might want to turn it over to a MINI indie for a total undercarriage exam. Bearings, bushings, ball joints and etc. Nuttin lasts forever. Min goes in every 5K regardless and they give they li'l guy a full 'turn your had and cough' exam. I will question if they send a sample in for a PSA count though.

 

I had a similar experience with mine, and I've heard of others saying the same. I ran FSD's for about 9 years/70K miles on my 2006 R52 (until I sold the car). It must have been a gradual deterioration that probably began at 60K miles or earlier, and I didn't realize it until the ride got really harsh.

I believe Koni has a lifetime warranty for original purchaser. You need a proof of purchase and ship them the old ones for reimbursing replacements.
http://www.koni-na.com/en-US/NorthAm...bout/Warranty/
http://www.koni-na.com/CorporateSite...f/warranty.pdf

 

The potential that (at 70K) bushings or ball joints seems real. But when I inspect all looks good. And I believe I'd have other symptoms (not just harshness).

FWIW I recently replaced..

• Rear upper shock mount bushings
• Rear SB end links
• Rear SB bushings

None of the above had any affect on the harshness.

Since I had the shocks out I was able to compress them by hand... I didn't have a new one to compare against so it's hard to say if it was normal but they seemed reasonably hard to compress. FWIW they look like crap. Very rusted with most of the gold paint gone. But no evidence that I could see of leaking.

 

I've also seen the FSDs begin to leak around that 50-60k mile mark on some cars, and some have noticed the ride deteriorating around that mileage as well. I've seen a couple of cars that have the FSDs begin to fail, seems to always be the rear shocks too.

But as stated; Koni does offer a lifetime warranty of them to the original purchaser. As long as the shock fails their dyno testing & inspection they should warranty the shock(s). Just know that the car will be down for 2 weeks minimum.