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Rear end noise question

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Old 11-05-2011, 11:39 PM
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Default Rear end noise question

I am super worrisome so sorry if this is a dumb question. Every time something breaks I freak out from every noise and clunk my car makes because I start listening too hard haha. I broke the drive shaft at the track the other weekend launching hard. I just put a new drive shaft in and took it down the road and noticed a "clunking" sound coming from what sounds to be the center section of the rearend. I only hear it when the car bucks at lower RPM's from the cam. It "clunks" with the bucking if that makes sense and only makes the noise when the car does so. I do have the rear seats out of the car so I seem to notice the noise more now. Is this just the backlash in the gear or something? I don't know a ton about this so please forgive my lack of knowledge. The rearend is a Moser 9" with tru-trac with a BMR torque arm ect. and is a M6. Thanks for the help!
Old 11-06-2011, 06:40 AM
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The T56 makes some cluncking noises, at least mine does.
Old 11-06-2011, 07:28 AM
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Originally Posted by 96lt4c4
The T56 makes some cluncking noises, at least mine does.
yeah, i know but this is coming from the rear of the car.
Old 11-06-2011, 10:26 AM
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anyone else?
Old 11-06-2011, 10:55 AM
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There is always slack in the rear end gears, some is normal. You have to think of all the moving, meshing parts your going to have slack some where. Mine has a clunk when I low RPM crusing/ bucking.

Would help to have a video.
Old 11-06-2011, 11:15 AM
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Originally Posted by RsSean
There is always slack in the rear end gears, some is normal. You have to think of all the moving, meshing parts your going to have slack some where. Mine has a clunk when I low RPM crusing/ bucking.

Would help to have a video.
Yeah, I wish I had a video of it.
Old 12-03-2011, 10:29 PM
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I think you are spot on with the backlash idea. With the bucking you are quickly increasing and decreasing engine speed. This causes the gear teeth to slap back and forth on the drive and coast sides, which makes a clunking sound. Try it under different steady throttle loads. If it doesnt do it under steady acceleration or deceleration it is safe to say that it is the cam bucking doing it.



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