Larry,
Thanks for the tips.

This drivshaft only has a shde over 40,000 miles on it after a remanufacture..at dissassembly, for the conversion to 5-speed, the u-joint was checked as you describe and was OK. When it was reconfigured for the 5-speed, it was retubed and balanced by a shop in San Antonio that has a good reputation for quality work.

Flex joints are questionable but, are the same ones that were in the 4-speed and it vibrated then too.

The shaft halves have never been apart since the driveline was reworked for the 5-speed and, there is no discernable dynamic vibration associated with shaft rotation.

I'm almost positive that the shaft is OK.

The vibration I'm encountering almost has to be harmonic since it has no connection to the wheel speed (and thus the rotation of the shaft) but, instead is closely associated with engine speed, being highly pronounced at 1800 to 2100 RPM in 2nd, 3rd & 4th. But, I have no idea what frequency it is.

Another forum member sent me a survey of Euro drivelines that he's encountered and the common denominator on the 5cyl/manual tranmission combination is a vibration absorber. PN: 123 411 17 47

I'm working on acquiring one of these jewels.

__________________
Never a dull moment at Berry Hill Farm.