NP993

Couldn't find much about this in the archives. The previous owner of my car put PSS9's on a long time ago, in 2002, somewhere around 80K miles ago. I've noticed recently that the rear ride quality has gotten terrible -- hard to describe, but a sort of "crashing" sound/feeling over bumps, even small ones, especially on rebound. It feels like the rear shocks aren't doing their job very well. (Although I must admit this is the first non-torsion bar 911 I've owned, so maybe I'm misdiagnosing -- although I've been under the car and everything else looks fine.)

Is this normal wear for PSS9's? I have the paperwork on the install from a decade ago -- does Bilstein really honor the lifetime warranty? I assume this would require putting my car up on jackstands for a while and sending the shocks in to be rebuilt? Anyone have experience with this and know how long it's supposed to take and how big a hassle it is dealing with Bilstein?

kjr914

From the following web address, with emphasis added:
http://www.bilsteinus.com/products/s.../warranty.html
So forget the warranty. For $125 or so each (when i checked a year or two ago) Bilstein USA in Poway, CA will rebuild them for you.

As for the durability, I know that mine were installed at 79k miles, I bought the car at 88kmi, and the (small, poorly designed) adjuster ***** were already broken (they just spin). This is a "known" weakness in the PSS9 design. No issue with ride quality, however.

I'm electing to put on new PSS10s since I don't want the crappy **** design and have to deal with them being broken again soon... Yeah, not a cheap way to go, however.

NP993

Ah, thanks Keith. I need to do a better job of reading the fine print. I guess when it comes time to do the suspension refresh, I'll just have them rebuilt.

jscott82

Cant speak directly to longevity... but deterioration is a progressive thing, unless something just breaks, its just a slow decline and since its slow you don't really notice it until its really bad. Since you (or the previous owner) have gone thought the trouble of installing high performance(we can debate what is high performance later) shocks, I would assume you want the best out of them.... 80k is way over that, I would be rebuilding them every 10k or 20k.

Bilstein is great though, I've worked with them on several projects and have been thoroughly impressed every time. and at $125 (I thought it was less than that) it's a bargain.

NP993

Thanks -- I don't think I'm going to rebuild every 20K, but you're right, 80K is too many miles. I'm wondering what the consensus is (is there one?) for the lifespan of PSS9's. Are they generally in need of a rebuild at 40K? 60K?

Steve Weiner-Rennsport Systems

These should be rebuilt around 80K to maintain ride quality & handling.

Kika

FWIW a set of PSS9s FS in RL classifiieds: https://rennlist.com/forums/for-sale...ein-pss9s.html

NP993

They need to be rebuilt, and they're for a Boxster, but otherwise, good tip.