major shudder during acceleration after shift

[doyle]

I have an '86 535i with 162K miles, auto with electronic shift control. Had a very bad differential (extreme gear lash and CLUNK when shifting into drive). Just changed the rear end. Prior to changing we had just started experiencing an extreme shudder when accelerating hard. It would occur either during accleration or after the shift. Letting off the accelerator eliminates the condition. Driving softly eleminates the condition. The change out of the differential was necessary and has got rid of the CLUNK, but the shudder is still there. It is hard to locate seems to be more rearward, but it's hard to tell. Rear U-joint had no visual problems. Appreciate any help on this problem before I soak a lot of money in the wrong place. Thanks. Doyle

[The Beastmaster]

Driveshaft could be bad as the u-joint is the non-serviceable type. Guibo could be going bad, or center bearing.