Giulia super 1970 driveline vibration

[robrexgreen]

Hi all , I've had a long running problem with a drive line vibration with my super  being worst at 40-50 mph. The driveshafts, uni joints and centre bearing were done at m+d driveshafts in sunshine a few years ago which surprisingly made no difference.The motor has just fully rebuilt by Sam at the Italian job and the gearbox checked. Today I dropped the rear tail shaft off and ran the car in the garage up to 40 mph vibration still there, then removed front driveshaft and donut,ran the car again with zero vibration.I can't see any problem with said shaft ie no movement in the bearing and the donut is in good condition.Can anybody help me out , would be much appreciated, Rob Park

[105gta]

Most likely the ball on the end of the gearbox that centres the driveshaft has worn flat spot on its outer diameter. Also the corresponding socket/cup in the end of the driveshaft has worn too. Both can be repaired.

[robrexgreen]

Great thanks 105gta I'll check that asap cheers

[MD]

"Had the shafts balanced.." doesn't necessarily cut the mustard. I have had shafts made from new and the manufacturer could balance their own shaft !! Had to have a third party finish the job. Had a Berlina once that went fine until you started peddling past 180 and then the whole rear end wanted to part company. Changed boxes, changed complete rear ends, balanced shaft wheels, tyres blah blah. Nothing solved it other than less speed.

105gta + Check the shaft if it not bent for a start. Confirm balance with a third party.

[robrexgreen]

Thanks for that , sounds like I've just got keep at it until breakthrough, cheers and thanks