Planet-9

Thumping Sound When Backing Up

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10 captured repliesPartial discussion capture · Source accounts, not a confirmed diagnosis

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YOUR RESEARCHThumping Sound When Backing Up

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kind of sound you hear

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1
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Suspected cause: 0
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Reported cause
It was the kind of sound you hear when you mistakenly drive over a board (or other object in the road) and it kicks up under the bottom of the car.
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Thumping Sound When Backing Up

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Leading evidence: 'kind of sound you hear' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'kind of sound you hear' (1 discussions; 1 report identifying it and 0 suggest it). No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

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1 matching discussions · 10 captured posts examined · 1 partial discussions

Reported and suspected causes (1)

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kind of sound you hear

No successful repair reported for this finding.

1
Identified cause: 0
Suspected cause: 0
Reported fixes

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Discussions that report identifying 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.

Reported cause
It was the kind of sound you hear when you mistakenly drive over a board (or other object in the road) and it kicks up under the bottom of the car.
Original post Read captured discussion
Thumping Sound When Backing Up

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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.

Planet-9: 1 discussions

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Generation: 20261027T033922Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1Original post

I've had a strange experience occur the last two times I've driven my Cayman . Both times, the car had not been driven for 2-3 days. I started the engine, then shifted to reverse to back out of the garage. When I began to release the clutch and give it some gas, there was this loud THUMP from under the car. It was the kind of sound you hear when you mistakenly drive over a board (or other object in the road) and it kicks up under the bottom of the car. Both times, I put the gear in neutral, then back into reverse, and everything worked fine. But those two loud Thumps have me concerned. Has anyone else experienced this or have an idea what it could be? I'm adding it to my list when I go up to the dealer, but the chances of them repeating that sound are probably nil because both times I heard it was on a cold first start.

POST 2Original post

Sometimes if I have washed my car and let it sit for a few days my brakes stick to the rotors. When I back out of the garage the brakes break loose and make a pretty loud noise. I might call the sound a thump. I'm not sure.

POST 3Original post

GfSpencer The first time it happened was three days after I had washed it. Maybe that's what happened. But I'm not sure what caused it to happen today.

POST 4Original post

Any of these help? 1. http://www.planet-9.com/cayman-complaints/8362-strange-noise-while-backing.html 2. http://www.planet-9.com/cayman-complaints/9838-mechanical-binding-when-backing-up.html

POST 5Original post

Santa Fe: NO No, these posts don't relate. The loud THUMP I hear occurs just as I'm lifting my foot off the clutch and giving it gas. It sounds like it's underneath the car. Both times I heard it, I immediately stopped and shifted back to Neutral, then shifted to reverse, and backed out without a problem.

POST 6Original post

Its your rotors sticking is all. Happens all the time. G.

POST 7Original post

As said, this is likely your pads sticking to slightly rusted over rotors. there have been several other threads about this in the past - a quick search should uncover them. this happens not only after washing your car, but sometimes in very damp weather, too. brad

POST 8Original post

Definitely the brakes. Happens all the time to me. Especially after sitting in the trailer for a while.

POST 9Original post

Try easing into the garage and stoping with the e-brake. I have to do this after washing my truck. My truck sticks so bad that I have to put it in 4wd to break the fronts loose. (drums in the rear).

POST 10Original post

Thanks, Everyone! Well, I guess this is just normal sound and it happens after sitting a while or after washing the car. Maybe this post will help others with this problem.

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