Help!!! car vibrating..

[NAT9566]

as you would know, i am a newbie.....
my car has a couple of issues... its a 1989 520i manual and vibrates badly at 90kmph/ 55-56 mph, what could possibly be wrong... my mechanic says its because the propellor shaft coupling has been welded to the differential coupling at the rear axle instead of being bolted/ pinned.... any ideas ?

on another note my car came with e39 r16 215/55 profile tyres and rims... is that too big.... as i was caught for doing 120 kmph in the 110kmph zone when my speedo showed 109kmph?

[shogun]

I suggest you to carefully read this page and bookmark it.
http://www.bmwe34.net/e34main/troubl...will_break.htm

I cannot imagine that the drive shaft has been welded onto the differential.

On my website below there is a tire and wheel calculator, where you can indicate the original combo and the required combo and the speed selection and then you see the difference. It is in German, but you will also find it in Englisch somewhere.
http://www.duetto-club.ch/d_kalkulator.htm

[Gayle]

As spokesperson for the clueless, I know nothing about wheel sizes but I do know that lots of people have vibration issues when they switch wheel sizes. You might want to use the search the forum tool at the upper right and do a search on shimmy and do a another search on hubcentric rings.

Welcome to the board.

[NAT9566]

err checked all those things.. and found no solution..... where there was supposed to be a pin there's welding... and i am taking the car to the specialist for a full diagnosis...
and just found out that the car vibrates as badly at 90kmph as well as at 130 kmph

[632 Regal]

well Nate sounds like your screwed, is there any way to post a picture of where this is welded? With pictures I know things can give more clues.

[NAT9566]

well Nate sounds like your screwed, is there any way to post a picture of where this is welded? With pictures I know things can give more clues.

will try to post over the course of the week... sending the car to the service centre is a major cash burner..oh well will have to do it...

[Incantation]

putting 16's on .. shouldn't make much of a difference if any.. you need new upper thrust arm bushings. problem solved.

also.. because the e39 hub is different make sure you have some hub-centric rings between the rim and hub.. if you have nothing in there you will experience mad wobbles.

[NAT9566]

putting 16's on .. shouldn't make much of a difference if any.. you need new upper thrust arm bushings. problem solved.

also.. because the e39 hub is different make sure you have some hub-centric rings between the rim and hub.. if you have nothing in there you will experience mad wobbles.

hoo makes sense.. thanks dude ...will get on to it asap and will up date...
and the welding problem is just part of it... will get pictures soon