Undetected clunk/banging
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From: Ft. Myers, FL
Undetected clunk/banging Car in sig. Has BMR TQ arm w/relocation bracket, Sphon LCA w/relocation bracket, Trackbird PHB, DMS lowering springs.
This is driving me nuts..I have had the car on 2-post lift and drive-on lift and can't locate or duplicate banging. Here's when it does it - slight bumps (ie reflector in road, my gravel driveway) does not do it on larger bumps (ie pothole, dips, etc). It IS NOT the typical f-body/y-pipe bang. Plenty of clearance there w/new poly motor mounts too. I have tightened and greased everything. Tending to believe its the TQ arm, but can't figure out where/why. Only does it when rear suspension moves (slightly as stated above) and on down shifts with built tranny.
Open to any and all suggestions. Thanks,
This is driving me nuts..I have had the car on 2-post lift and drive-on lift and can't locate or duplicate banging. Here's when it does it - slight bumps (ie reflector in road, my gravel driveway) does not do it on larger bumps (ie pothole, dips, etc). It IS NOT the typical f-body/y-pipe bang. Plenty of clearance there w/new poly motor mounts too. I have tightened and greased everything. Tending to believe its the TQ arm, but can't figure out where/why. Only does it when rear suspension moves (slightly as stated above) and on down shifts with built tranny.
Open to any and all suggestions. Thanks,
Any chance you could get a video of the sound? Can you post a picture of the underside of the car so maybe I can get an idea of what may be causing it?
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From: Ft. Myers, FL
Sounds like someone laying under car with a hammer! I spoke with someone from BMR last week and they said could be TQ arm/lowered car combo. When on a drive-on lift the TA is within approx. 1/4" of tunnel. On my 2-post there is a shiny area in tunnel that I have tried clearancing some. If that were the area it would (imo) sound more of a scraping. I will try to get some sound vid and pics on my 2-post. This thing sounds like a clapped out farm truck on my short gravel driveway, yet quiet on pavement (unless you hit a reflector or surface change). Weird
On second thought, I may try temporarily wrapping the TA in the suspect area and see if it quietens it some...
On second thought, I may try temporarily wrapping the TA in the suspect area and see if it quietens it some...
Do you have the adjustable torque arm mount crossmember? Where is it set? Are you able to see the top of the torque arm to see if there are any rub marks on it? I'm sure you have, but have you checked the hardware on the trans crossmember and such to make sure nothing has come loose? I just ran through this issue on my personal car. Was driving me crazy for a couple of days before I discovered 2 of the bolts had backed off some letting the crossmember move up and down and bump the floor.
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From: Ft. Myers, FL
I just installed a new tranny last Sunday, so all TA and relocation bar was removed. Put everything back together with impact to assure tight and rechecked everything (it was doing it prior to tranny change as well). I happen to have a pic of where it is currently set. I will triple check everything again tonight and may try the rag around TA in suspect spot for fun.
Looks like you have it all the way in the top mounting position. could you try dropping it down a hole and see if that makes the noise go away? also looks like the bolt bosses on the tailshaft housing are very close to the t/a mount. Is it possible they are making contact? Looks like some marks on it. Try loading the rear suspension with the car on the lift and see if you can run your hand around the t/a and find any clearance issues
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From: Ft. Myers, FL
Rag around TA in suspect spot did not make it go away. I can try mounting a hole lower but the suspect spot is at the very rear (I took some pics and will post tomorrow). The heim joint mount points do appear to be touching and I think a flat washer is needed there. I also checked every nut/bolt point and all is so snug couldn't move any. I, for the life of me, can't find any other contact points. Thanks for your insight.
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