driveshaft balancing

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Robert Bondi
Posts: 362
Joined: Sun Jan 11, 2009 12:33 am
Location: Austin, TX

driveshaft balancing

Post by Robert Bondi »

Anybody know how seriously to take the blue book statement that the driveshaft is balanced as a complete assembly?
I have the driveshaft out on my resto car. While moving it around, the two halves separated before I had the chance to mark how
the splines lines up as all the manuals recommend.....
Robert
77 530i
77 Euro 528
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Lock
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Location: Olympia, WA
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Re: driveshaft balancing

Post by Lock »

Driveshaft pieces are usually balanced independently, just like your tires are balanced independently, so you can generally mix and match.

What's crucial is that the universal joints are in phase, so if you didn't mark when the splines go, ensure that the 'arms' of the u-joint on the shaft line up exactly. When the shaft is angled, the center speeds up and slows down relative to the input/output and if not exactly matched will cause vibrations and damage.

Image

https://powertestdyno.com/proper-drives ... alignment/
1979 528i - Sold
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Robert Bondi
Posts: 362
Joined: Sun Jan 11, 2009 12:33 am
Location: Austin, TX

Re: driveshaft balancing

Post by Robert Bondi »

Excellent! I was hoping for a nice DIY guideline since I think the two sections are still nicely balanced and the weights are present.
Thanks.
Robert
77 530i
77 Euro 528
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