dnwong

I am looking to purchase an 996 with the following mods:

Bilstein PSS9 Coilovers
H&R Sway Bars (Front and Rear)
GT3 Strut Mounts
AP Drop Links

When I took the car out for a test drive. The suspension makes a lot of noise especially going over rough roads. (sounds like the springs are loose). The owner said he had a PPI done and the noise was not flagged as an issue.

Does this seem normal?

Sneaky Pete

Don't trust an owner of a car for sale that does his own PPI.

alpine003

How low is the car? Tender springs can compress over time, especially considering the pss9 model is quite a bit older.

Did the PO use the correct adapter for the pss9 to use with the GT3 strut mounts?

Fwiw, my gt3 co's have always made noise but have only discovered it when I took out the carpet.

Other than that, does it handle good? Any signs of oil leaks from the shocks? Did you try wiggle the drop links for any play?

tokyopav

Mine makes the same noise I think. Almost plasticy but metallic a little. I'm guessing drop links. Handles great still. Only hear it at low speeds on rough roads.
Mine also passed a Japanese mechanical check recently and no problem found.

LordVicious

It's certainly not surprising that a 10 to 15 year old car makes some suspension noise. Can you describe what kind of noise (I don't know what a "lose spring" sounds like)? Noise from old, failing drop links yields a "creaky ship" sound.

tokyopav

Mines a definite rattle noise.

LordVicious

You really need to get under the car and start grabbing stuff until you figure out whats rattling. A "rattle" could be anything from exhaust to motor mounts. This is where a rubber mallet comes in handy.

DBJoe996

If someone installed the brake pads without the dampers (which is very common), the pads will chatter, or kind of rattle, against the rotors at low speed and rough road. Not a problem but it does make a particular noise that one might suspect would come from a suspension component.

p.vanderlinden

Interesting, I've never heard of that cause.

Mine has pss9 or 10 and makes noise on rough or cobblestone like roads at low speed only <15-20 mph). Same thing on my BMW which has coil overs.

I have checked all links for play and have found none.

Will try lightly applying brakes next time to see (or hear) if there is a difference.

Paul

dnwong

I guess this is starting to sound like a normal noise. Maybe those AP drop links which seems to be problematic. Car handles fine and the noise is apparent on low speed rough roads only. Just wanted a sanity check before considering buying the car.

alpine003

Most if not all coilovers using spherical bearings in the strut mounts will have noise, especially on low speed bumps as you're describing.

WalterRohrl

Make sure you do your own PPI at a different shop than the owner used and ask them to pay special attention to the noise. It would be helpful if that shop has direct familiarity with the PSS9/10 system obviously.