E28 Driveshaft shake

[Dave Allan <elmospad@xxxxxxxxxxxxxxx>]

Hello ,
      I have an '88 535i with approx. 70k which suffers from a severe
shake at about 35mph . The shake is very bad when the car is driven
after sitting overnight and gradually goes away entirely after about 10
mins
of driving , sometimes longer if the weather is cooler . The shake seems
to come from the driveshaft and is only noticeable at the speed
mentioned above , it is a 5 speed and has recently had a new guibo
installed .
Any ideas ? Has anyone had the same problem ? The shake is the same
regardless of the gear and improves slightly if the car is accelerated
quickly through 35 mph , any help would be appreciated .
Thanks in advance ,
Dave.

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