THSCC Forums

I recently replaced the driveshaft on my 91 318is with a low mileage rebuild. Since I had everything out I replaced the center support and flex disc also. Now I have a low speed dependant vibration and noise right around 20mph. Any suggestions where to look next? The tranny mounts were in pretty bad shape so they are already on the list.

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2004 Ranger Edge
2003 Buell XB9R
2004 Trek 4900
2004 Specialized Stumpjumper FSR Expert Disc
2004 Lemond Reno

I got a soft hum that in about 5 weeks turned into a roar when the differential went on my E30. I hope that isn't the case here. - AB

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'14 Toyota Sequoia Platinum 4WD
Super Westerfield Bros - '93 Integra - LeChump Du Jour
STX 93 - Scion FR-S

I dont think thats it. The noise is coming from around the flex disc area. Its been suggested I preload the flex disc by prying the center support closer to it. Since I didnt have the book with me its probably a step I missed.

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2004 Ranger Edge
2003 Buell XB9R
2004 Trek 4900
2004 Specialized Stumpjumper FSR Expert Disc
2004 Lemond Reno

I'm no expert on the subject, but I remember hearing that the driveshaft balance is critical to everything running smooth. Since you replaced everything else that typically is problematic, could you have a bum driveshaft?

The driveshaft is balanced with both pieces together. If you pulled it apart at the splines and didn't mark it to put it together in the exact same way, I think that would cause an imbalance.

Just a thought. If you don't figure it out give Truett Ray or Dietrich at Shade Tree Garage a call - they're a great independent BMW shop

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Mike Whitney
whit32@gmail.com, 919-454-5445
V10, V8, V8t, I6, I6, V6, F4t, I4, I4, I4, I4, I2, 1, 1

Its possibile that its a bum driveshaft. I want to try the preload thing first before I start looking for another one. The driveshaft was already marked since it was a rebuild and I made sure to get it back together with the marks lined up. I hate to call Truett knowing I will probably not be taking it up there for the work.

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2004 Ranger Edge
2003 Buell XB9R
2004 Trek 4900
2004 Specialized Stumpjumper FSR Expert Disc
2004 Lemond Reno