10 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHDiagnosis - rumble and clunk
Reported or suspected cause
blown rear shocks
Suggestion or failed attempt
No successful repair reported for this finding.
0
Identified cause
1
Suspected cause
0
Reported fixes
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that suspect a cause
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suspected cause · Original poster
We were unable to reproduce the vibration I had experienced but now suspect the blown rear shocks to be the culprit here.
Leading evidence: 'blown rear shocks' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'blown rear shocks' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Check torque' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
Check torque on the bolts at Transmission output flange!
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
10 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261027T022239Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
I was on the highway in my '03 C2 yesterday motoring along at 75 mph. A low rumble started in the back of the car. At first I thought it was a rough patch of asphalt but soon the rumble got louder and my rear view mirror started to blur. I quickly pulled to side of road but found no visible problems. Engine ran fine and no noises or leaks. Got back to speed and sound was gone. Drove straight home and now notice a clunk sound from the back in turns and over uneven road patches. Any thoughts on what to check?
Thanks,
David
Best advice I can offer is to get the car to a place and get it lifted in the air with the tires/wheels unsupported.
Then under the car give the tires/wheels and suspension/drivetrain a thorough inspection.
Could be something like a wheel lost a balance weight to a tire coming apart or a cracked/bent wheel to a failing CV joint bearing to name the possible explanations that come quickly to mind.
Will update soon. Drove my sons car to work and have a more knowledgeable friend over on Wednesday to diagnose. Drove car up on blocks in anticipation.
Well the CV joints look fine. Everything is tight on the drive train and spinning wheels on the rack produce no bad sounds. Both rear shocks are leaking badly and are original (126K miles) - the entire suspension is original. We were unable to reproduce the vibration I had experienced but now suspect the blown rear shocks to be the culprit here. So I am now researching the suspension options.
I realize there are a million threads on suspension and I am reading them today. My wrench friend says I should pull the trigger on a 4 corner Bilstein HD setup with Euro spec factory springs. He says this would be a better setup than the ROW M030 kit sold from Suncoast. Going this route would also be $500-600 more expensive though. If anyone has thoughts on the matter I would appreciate them. Thanks!
No clue on the rumble, but I bet the shocks and tired sway bar links are to blame for the clunk. Personally I plan to go with the RoW M030 kit, which is a bargain for what you get. Factory Porsche shocks seem to make it pretty close to 100k before they wear out (at 95k mine aren't leaking), you won't get any better than that out of Bilsteins. Plus it is a factory engineered suspension package (as factory delivered in Europe), not combining ala-carte components that were not explicitly designed to work together.
One other note of interest, I was looking up another part in the online PET and noticed that all of the standard and M030 shock absorbers for the 996 show up as "shock absorber - bilstein".
This is a source reference. Confirm exact model applicability in the original material.
