Syncro driveline vibration

[iceracer]

Ok, paging Syncronauts!!! My 86 syncro had the original driveshaft in it and all was well, no vibration. I bought a slipyoke type a year ago thinking I would need it and I finally started to get some vibes around 40mph. So pulled the old and one to two joints are stiff. Threw in the slip yoke and now have much more vibing. Marked the diff and tranny so all was in the same orientation going back together. Without it in there, the syncro in 2wd is smooth as can be. So I can rule out tires, suspension etc and anyway all that was done 1-2 years ago. So could it be the new shaft is out of balance? What do you suggest??? Thanks.
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86 Syncro Wolfsburg edition
63 Beetle (The Iceracer)

[gears]

If it were me, I'd do what someone else suggested, and put one or more hose clamps on the shaft, and rotate them until the vibration disappears. If the vibration is affected, it was a matter of the shaft being out of balance.

[zippyslug31]

This might be a bit far to go with potentially no payoff, but when refitting my shaft/trans/engine back in after a rebuild, I also cracked the front diff loose (I think 2 or 3 mounting points if memory serves), tightened the drive shaft both front and aft thus making the entire drive line 1 fixed unit, THEN tightened the mounts for the front diff and rear trans/engine.

Again though, this was because I already had those loose in the first place.

In the end, it had no vibration issues.
Your mileage may vary.
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previous:
'80 westy
current:
'90 syncro westy 2.5L subi, triple knob, 16" wheels.
'84 sunroof van, 2.1L motor.

[iceracer]

Thanks for the info, I think I will try to see if someone here locally can check the balance on it and if it is off, then reinstall and see. After that, will try to loosen diff up front and readjust. Sucks since never had this problem before. I can live with it as is but it still bothers me, should be smooth, just one of those things that eats at you.
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86 Syncro Wolfsburg edition
63 Beetle (The Iceracer)

[zippyslug31]

Don't sell yourself short. I think it's more than something you are being picky about.... vibrations over time can lead to premature wearing on parts or at the very least loosen the mounting bolts.
_________________
previous:
'80 westy
current:
'90 syncro westy 2.5L subi, triple knob, 16" wheels.
'84 sunroof van, 2.1L motor.

[Christopher Schimke]