Thumping under the floorboards?

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Sep 2, 2008 | 12:30 AM

96tealTA

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Thumping under the floorboards?

When I launch, or if I floor it and the trans. downshifts to first, I get a weird thumping noise from the floorboards. Is it time for a new trans. mount or what? Oh, and it didn't do that before I had longtubes.

Sep 2, 2008 | 12:50 AM

torquejunky

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its the headers/Y, it might be time to massage the floor pan, I'd try playing with the y-pipe first though

Last edited by torquejunky; Sep 2, 2008 at 11:01 AM.

Sep 2, 2008 | 08:19 AM

slowmofo

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yep, its your y-pipe hitting your floorpan.. It was a big problem in my 94 till I used a BFH mod..

Sep 2, 2008 | 09:08 AM

THE CHOP SHOP

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Could very well be the y pipe. I would take a look at your trans mount though. Mine was shot at 60k. Pretty much ripped in half and barely hanging together. I got a energy suspension poly mount from autozone cause they had it on the shelf.

Sep 2, 2008 | 09:24 AM

Caveman

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Losen the the clamps on the Ypipe +header and use a 3' pry bar to get a gap between the ypipe and floor board then retighten header and ypipe clamps.

Sep 2, 2008 | 09:25 AM

fenix999

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either y-pipe is hitting or your trans mount is fubarred, or both.
good luck

Sep 2, 2008 | 10:24 AM

crazykid

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Sep 2, 2008 | 08:32 PM

96tealTA

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Just bought a tranny mount. So I'll try that first, and I'll let you guys know.

Sep 2, 2008 | 08:44 PM

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crazykid

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You can generally see if the mount is broke or not, you will see rips and cracks in the rubber. 9 times out of 10 floor board thumping is caused by the mount. Let us know if it fixes it.

Kyle

Sep 2, 2008 | 09:06 PM

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gator's 99TA

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Quote:

Originally Posted by crazykid

You can generally see if the mount is broke or not, you will see rips and cracks in the rubber. 9 times out of 10 floor board thumping is caused by the mount. Let us know if it fixes it.

Kyle

listen to this guy. Kyle is the ONLY guy that is allowed to work on my car.

Sep 3, 2008 | 08:13 AM

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bboyferal

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Quote:

Originally Posted by gator's 99TA

listen to this guy. Kyle is the ONLY guy that is allowed to work on my car.

My motor agrees!

Sep 3, 2008 | 08:27 AM

#13

slowmofo

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From: Melbourne, Florida

yeah but it didn't start till he put the long tubes on, and the tranny mount is more of a banging in the tunnel, not the floor board..

Good luck OP let us know what you find..

Sep 3, 2008 | 09:05 AM

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SSJIMMY

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I will have to look at my tranny i have had the banging for a while now and just figured it was my y-pipe. how much is the mount not to much I would guess.

Sep 3, 2008 | 09:13 AM

#15

Eroc

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From: Fort Worth, Texas

Trans Mount... Y-pipe would be one Thump at hard launch...

Tq Arm is kitting the Floor Pan I bet...
Trans Mount is none existant anymore...
You need to fix this ASAP...

Change in launch Angles can/will damage drive line and rear end.. also undo wear...

had this issue with my 89 ROC...

Sep 3, 2008 | 09:29 AM

#16

slowmofo

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From: Melbourne, Florida

Quote:

Originally Posted by SSJIMMY

I will have to look at my tranny i have had the banging for a while now and just figured it was my y-pipe. how much is the mount not to much I would guess.

poly mount is only like 20 bucks

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Thumping under the floorboards?

Thumping under the floorboards?

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