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Under car clunk on decel *searched*

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Old 04-22-2010, 08:51 PM
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Default Under car clunk on decel *searched*

Basically it feels like something is clunking the cars underbody right under my ***. Only does this at low rpm on decel. Ive gotten under the car and EVERYTHING checks out. Kinda stumped. here are my notes:

- Panhard bar is tight
- tranny mount looks ok, shifter does not go up and down
- poly motor mounts
- torque arm is tightened down good (Spohn)
- BMR LCAs are tightened down good
- SFCs are welded on

Now im thinking it COULD be the Spohn torque arm as I know a lot of guys have the clunking deal with it. It is more of a nuisance than anything really, but its definitely noticeable. I have an HPDE event this weekend but im not too worried about it, i doubt ill be in low rpms and decelerating, lol. Any thoughts? Could it be a loose drive shaft? teeth missing in the gears?
Old 04-22-2010, 08:55 PM
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I'm thinking it's your gears or differential. I had the same noise for yrs then it just went away. However that was my differential I'm sure. Maybe pull the rear cover and take a look.
Old 04-22-2010, 09:03 PM
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Originally Posted by rich Z
I'm thinking it's your gears or differential. I had the same noise for yrs then it just went away. However that was my differential I'm sure. Maybe pull the rear cover and take a look.
I have my doubts about the differential because if i drop 190lbs of me into the seat fairly hard it will make the same clunk (although much quieter) lol
Old 04-22-2010, 09:21 PM
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Have you checked your U joints ?
Old 04-22-2010, 09:24 PM
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bushed or rod end's on the torque arm? if its rod ends, im guessing thats it. Ive got rod ends on my Midwest torque arm, and double adjustable lower control arms (with heim joints on both ends) and i get all sorts of clunking and banging back there.
Old 04-23-2010, 01:12 AM
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Check the drive shaft/ U joints.
Old 04-23-2010, 06:13 AM
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What's the easiest way to check the u-joints?
Old 04-23-2010, 08:43 AM
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Originally Posted by OffspringZ28
What's the easiest way to check the u-joints?
Get under the car and twist the drive shaft side to side. Look for slop/movement inbetween the bearing cap and the center cross.



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