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So I have a 2000 323i and from 0-20 mph a loud thumping sound comes from the middle of the car and typically goes away after 20 and is only when I accelerate. I’m thinking it’s the drive shaft any suggestions
 

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2004 325i automagic
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A bad center support bearing would allow the center of driveshaft to move/flop around. A failing driveshaft flex disc (aka giubo) at the transmission could also be falling apart and allowing movement.

Unless the driveshaft was serviced or removed recently and reinstalled incorrectly, it wouldn't normally go out of alignment unless one of the above happened.
 

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2004 325i automagic
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Thanks can I drive it before getting fixed
If its not too late already, you risk trashing the driveshaft u-joints the more you drive it ... drive it to the shop, sure, but don't put off repairing it.
 

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E30M3 Race F10 535 R1150Rt M Coupe
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Be advised about the good advice above.
About 50% of the time the reason the center support bearing goes bad is due to a universal joint (some driveshafts have 2) with a binding spot.

When you have the driveshaft out, articulate both universal joints through their range of motion. Any stiff spot, becomes exponential with torque applied. This sends second order forces (vibrations from sticking/release) through the driveshaft and into the center support. It's supposed to absorb such, but can handle only so much.
 

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Happened to me when I first got the car. U joint was toast and threw the center support bearing out of wack and exploded underneath the car. You'll need a new one most likely, and get one from driveshaft specialists. They make good driveshafts for a good price
 

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Happened to me when I first got the car. U joint was toast and threw the center support bearing out of wack and exploded underneath the car. You'll need a new one most likely, and get one from driveshaft specialists. They make good driveshafts for a good price
+1 on Driveshaft Specialists of San Antonio, Texas.

I had a binding u-joint on mine and installed one of their rebuilds. Worked out great. New CSB pre-installed and they had a good deal on new flex-discs also. Once you get the exhaust off (assuming no issues with rusted fasteners) its a DIY of moderate difficulty, since it does require some care in setting CSB preload, making sure the flex disc is bolted correctly to transmission flange, making sure the driveline is lined up straight, and that you use the proper torque for the rear diff flange bolts, which can be tricky to look up. Its not really diffucult, you just need to pay attention to certain details, but I wouldn't necessarily recommend undertaking it unless one was comfortable DIYing a suspension.

Good time to change transmission mounts as well ... plus service the rear diff mounts or even the entire rear suspension if you are geared up & motivated for that sort of thing.
 

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2003 M3 6MT Slicktop
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sounds a lot like the “guibo”.
that’s the usual and more common rubber part that wears out and fails. next and often a casualty of this is the CSB.
 
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