Loud noise from under car in heavy rain!
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Just bought my '05 V and was driving it into work this morning and hit some heavy rain when all the sudden this loud noise from underneath car started happening. Almost like some sort of a vibration or grinding noise. It stopped and when I got out of the heavy rain, but started again when I got into some more of the heavy stuff (then it quieted down once I hit a dry area). Has anyone else experienced this or know what it is? Could be the traction-control system.
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Probably just rain hitting the inner skirts in the fender well or splashing up into the car. I will make a mental note to turn the radio off and listen next time I'm in heavy rain.
As long as there is no noise in the dry I would say your ok. If the noise doesn't go away then panic.
As long as there is no noise in the dry I would say your ok. If the noise doesn't go away then panic.
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Thanks for the feedback. However, I don't think it was just water hitting the wheel wells, etc. I've owned and have ridden in dozens of car in my lifetime and have never heard a car make this sort of noise when driving in the rain. It sounded like it was coming from underneath where the transmission/driveshaft is and I could kind of feel it. It was a loud enough grinding sound that I heard it over the radio and had to turn it down to try to figure out what it was or where it was coming from. If yours was doing it, you'd know it. It was not normal rain noise.
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The car does have a Corsa exhaust system on it. Like I said, I just bought the car from a dealer last week so I'm still trying to figure what mods the previous owner did on it. I know he did the Corsa exhaust on it.
How do I tell if it's the full cat-back system? I assume it is, but don't know for sure. Also, what would this have to do with the noise I heard? Tell me more, please.
How do I tell if it's the full cat-back system? I assume it is, but don't know for sure. Also, what would this have to do with the noise I heard? Tell me more, please.
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if you have the Corsa exhaust tips you probably have the complete catback. it starts obviously right after the cats which are by the trans, goes to resonators (H pipe), then to the mufflers, and lastly to the Corsa tips. i replied to your PM
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Heh, I posted about this many years back.
Your corsa resonator is probabaly slightly loose. You go over a puddle, and water splashes up on the pipe, cooling it quickly which causes it to contracts. With the rest of the system still hot, it bends up and contracts into the drive shaft.
First time it happened to me, it scared the living **** outta me. I think I described it over on CF as a band of rabid monkeys hitting the underside of my car with some ballpeen hammers.
Check your resonator O-clamps, and validate that they are tight, and that the catback is positioned correctly.
-Chris
Your corsa resonator is probabaly slightly loose. You go over a puddle, and water splashes up on the pipe, cooling it quickly which causes it to contracts. With the rest of the system still hot, it bends up and contracts into the drive shaft.
First time it happened to me, it scared the living **** outta me. I think I described it over on CF as a band of rabid monkeys hitting the underside of my car with some ballpeen hammers.
Check your resonator O-clamps, and validate that they are tight, and that the catback is positioned correctly.
-Chris
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Just bought my '05 V and was driving it into work this morning and hit some heavy rain when all the sudden this loud noise from underneath car started happening. Almost like some sort of a vibration or grinding noise. It stopped and when I got out of the heavy rain, but started again when I got into some more of the heavy stuff (then it quieted down once I hit a dry area). Has anyone else experienced this or know what it is? Could be the traction-control system.
mine did the same thing last friday. i was driving in the rain and then it stopped raining. i came to a stop sign where it was completely dry and when i took off in 1st gear i heard that noise. i pulled over looked under the car and didn't hear nothin. when i pulled into my driveway i heard it. after i parked the car in the garage i pushed up and down on the front end to rock the car and you could hear it. i know it has something to do with the front suspension. it's only done it one time after that and it was dry with no rain whatsoever. i wonder what it is?
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well, we had 5 show up. 3 platinums and 2 ravens. it was held at a members house. He's tryin to make it a bi-monthly thing. where is the texas mile at? maybe we can set something up.
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I think the noise I heard was from my exhaust scraping up against the drive-shaft. I put it on a lift and could clearly see where the passenger side pipe was scraping. I guess the heavy rain/puddling water was/is causing the pipe to flex and making it move into the shaft. I took it to the dealership and they adjusted the pipe to give it more clearance. I don't know if that fixed it or not because I haven't hit any heavy rain since. Apparently this is a known issue with the Corsa exhaust, which I have... (link references trukk's rabid monkey post). I'll post an update as soon as I find out for sure.
http://cadillacfaq.com/faq/answers/corsabang.html
A-Bomb - I live in the Clear Lake area. If you're the same person that posted about the Houston Meet over on the cadillacforums.com site, I've been following that thread (actually replied in the thread - my nic over there egypt123 too) and it looked like a good time. Unfortunately, that weekend didn't work for me. I hope to hit the next one though.
http://cadillacfaq.com/faq/answers/corsabang.html
A-Bomb - I live in the Clear Lake area. If you're the same person that posted about the Houston Meet over on the cadillacforums.com site, I've been following that thread (actually replied in the thread - my nic over there egypt123 too) and it looked like a good time. Unfortunately, that weekend didn't work for me. I hope to hit the next one though.
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It is really comical how common the CTS-V and my Volvo S60R really is. We use the same exact caliper/pads, and we have the same rain squeal problem with a resonator on the drive shaft. We also share diff problems, slave cylinder issues.. Yet I still want an 07 CTS-V with low miles!!! You just can't beat that engine, and trans combo and I love the styling of the V.. someday soon my R will be gone and the V will be here.
#18
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It is really comical how common the CTS-V and my Volvo S60R really is. We use the same exact caliper/pads, and we have the same rain squeal problem with a resonator on the drive shaft. We also share diff problems, slave cylinder issues.. Yet I still want an 07 CTS-V with low miles!!! You just can't beat that engine, and trans combo and I love the styling of the V.. someday soon my R will be gone and the V will be here.
![](http://www.cadillacforums.com/forums/attachments/2004-2007-cadillac-cts-v-performance/35368d1182889021-tiffany-not-amused-database-hosed-type_argh.jpg)
-Chris
P.S. I got some titanium brake shims based in part off the recomendation of the S60R crowd
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The shims are good but our pads come with the shims built on them.. but they still squeak some.. even with a crap load of lube.
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Not sure why the last pic didn't come through. Here is is again (uploaded to this forum):
![](https://ls1tech.com/forums/attachments/cadillac-cts-v-2004-2009/200792d1255108889-loud-noise-under-car-heavy-rain-type_argh.jpg)
-Chris