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View Full Version : HELP Front end vibration won't go away



Tiger
05-15-2008, 09:41 PM
Typical Thrust arm bushing is shot... vibration at around 55MPH... if you brake at this speed, it feels like your whole front end would fall apart...

Change the thrust arm and bushing (Upper control arm).

Best set is Lemforder with M5 bushing
Second best is Lemforder with Boge 750iL bushing.

535BOY
05-15-2008, 10:13 PM
OK I'm at the end of my rope. 1989 535i 5spd. running 225s on the front.Had a terrible violent shimmy at 45mph so did the obvious, new struts,complete front end rebuilt, tires changes twice aligned 3 times and finally tires have been balanced numerous times. the problem is much better but now at about 50mph I get the same shimmy (though tolerable) it's still there till about 60-65 and it smooths out. It seems to be coming from the right side front but have check all bolts for proper torque. The only thing that I have not changed is the drag link and idler arm.The rims are aftermarket but was told that I did not need hubcentrics, t or f ? Has anyone had this problem ? I'm really frustrated, other than this shimmy it's a great car

uscharalph
05-15-2008, 10:20 PM
I'd make sure about those rims. The hub diameter has to be right.

535BOY
05-15-2008, 10:28 PM
Yea it done it with 2 different sets of rims, before and after the front end rebuild

Paul in NZ
05-16-2008, 02:58 AM
2 different sets of rims maybe but were they the correct wheels for the e34?

Tiger
05-16-2008, 07:45 AM
yes... It doesn't matter how many sets of wheels you try. It will have same result with thrust arm bushing shot. If not the thrust arm bushing, then the thrust arm ball joint is the cause... that's why you change them whole.

BMWCCA1
05-16-2008, 08:17 AM
Thrust arms are the usual suspects, and good to replace if you don't know how old they are or they look to be original. But don't overlook rotors. You don't have to be on the brakes to get the effect of an out-of-round rotor. It just gets worse when you hit the brakes. And bad thrust arms will make it even worse.

Tiger
05-16-2008, 09:02 AM
Unless the wheels are for E39 and without the proper shims, the wheel will vibrate also at the same speed...

SnakeyesTx
05-16-2008, 10:42 PM
I'm inclined to agree about the thrust arm bushings. I went with 95 740/840 bushings instead of the OEM liquid filled craptacular ones. They press right in and they work great... and are solid instead of that silly-cone crap.

Paul in NZ
05-16-2008, 10:55 PM
but the wheel/tire balance and good tyres are critical too..out of no where i had the shimmy bck and it was violent right on 95 km hr,could acellerate trhough itt or a slight turn or could even brake out of it....new tyres(needed new back tyres so the fronts went on the back (same side) and the new tyres went on the front and the two best rims went onto the front,balance,alignment...smooth as glass again.You must make sure
1) the rims are as good as you can get,the two best always on the front(if they have bends) and they are the correct hub dia(use rings if you need to.
2)The tyres are good,ie no manufcturing iregularities,etc and tyre/wheel is well balanced
3)thust arm bushings are good.
4) tyre pressures are good and alignment is good.
the first three are fundamental to a non shimmying e34

derf_roa
05-17-2008, 03:35 AM
it could be your brake rotors are warped already. also try switching to your stock rims and drive for a day to figure out whether it is from your rims or a suspension piece. also check ball joint, center link. but you probably did already if you had a whole front rebuild.

hey if find out the solution to the problem post it up ok.

thanks

dog man
05-17-2008, 04:48 AM
Hi 535BOY,

I'd say try the following: Check the lock nut at the bottom of the steering column - this will feel tight most probably but if you are able to move your column in and out freely then this tells you it could tighten up a bit. Tighten it so that the column slides in and out with slight resistance, too tight and it wont move at all!

Also drain and refit new pas fluid, I did this recently on mine and it has made a noticable difference (depends how old my fluid was, yours might not be as bad/old)

Do fit a new drag link and especially idler arm, you cant diagnose it properly if you know there are 'old' bushings on there still and as long as its not a problem with your wheels/tyres I'd be pretty sure this will fix it.

Did you get the rears balanced also?

HTH

BMWDriver
05-17-2008, 07:54 PM
I had rust on the brake discs that caused a shimmy when using them. The car was parked a few days under rain. A couple of very hard braking stints solved my issue.

It's something we should do every once in a while - as per the owner's manual. Just don't do it at the first braking manoeuver, cold discs could warp.