Vibration throughout whole car at around 55MPH

[Paul_540i]

I've heard of this loads, and I definitely have it! My E34 feels like the wheels are out of balance, but all 4 were just done. It is worst around 55-60 MPH, but is very dependant on the road surface, whether you're going straight etc. Sometimes it feels quite bad others it's almost unnoticable. It is sometimes felt at as low as 30 MPH.

What's the most likely culprit? I'm suspecting some kind of suspension bushes probably at the rear, as the vibration is through the whole car rather than the steering wheel. There are no knocks or rattles from the suspension though.

Cheers
Paul.

[crashnburn80]

Its probably your thrust arm bushings, they almost always fail and cause the 50-60mph shimmy. When replacing them you can use E32 750 bushings which are stronger.

[philbyil]

If you don't, you might need hubcentric rings (they may have been lost on the balancing!) If you do have stock wheels, then most likely it is the Thrust Arm Bushings. One quick and easy way to test is to have someone drive your car slowly then hit the brakes...if you see the front wheel move rearward..it's the bushings.

[GM525]

Hi Paul,
Know exactly where your coming from mate. I had the same problems with my e34 525ixT. It turned out that although the balances were ok, the n/s/r rim was out of shape. I managed to rework it myself. Now its loads better but very slight vibes between 55-60 mph. From what you say , you definitely have a rear end prob as it can be felt through the seats and not the steering wheel.
Anyway, I would be looking at the prop, centre bearing or driveshafts, but would prove difficult to diagnose.It would be well worth jacking up the rear and check wheels,bearings,shafts, bushes and centre bearing for freeplay/wear.
As for me, I have learned to put up with it and avoid 55-60, especially as the 4WD e34's getting thin on the ground and parts are scarse.
Good luck.

[GJPinAU]

Paul,

I had the same problem with my car and found out it was the tyres. I've had my car lowered and this had changed the camber on the wheels, which in turn had worn the tyres on the inside and was not visible on the outside (80% worn), it wasn't until I had it put on a hoist that I had noticed the rears were down to the canvass and the fronts weren't much better. This was after travelling from Sydney to Queensland (1000kms at around 110kph most of the way) fully loaded with wife and kids.

(There, that got that guilt trip off my chest.)

,
Greg

[MBXB]

Paul,

Start with the upper thrust arm bushings, then check your center link. In my case, my 540 had over 140K miles, and it was both the upper thrust arm bushings and the centerlink. I changed everything. I figure that leaving a weak link (old component) will just accelerate wear on the entire steering/suspension system.

Ramon
MBXB

I've heard of this loads, and I definitely have it! My E34 feels like the wheels are out of balance, but all 4 were just done. It is worst around 55-60 MPH, but is very dependant on the road surface, whether you're going straight etc. Sometimes it feels quite bad others it's almost unnoticable. It is sometimes felt at as low as 30 MPH.

What's the most likely culprit? I'm suspecting some kind of suspension bushes probably at the rear, as the vibration is through the whole car rather than the steering wheel. There are no knocks or rattles from the suspension though.

Cheers
Paul.

[BobbyRitz]

Paul,

Start with the upper thrust arm bushings, then check your center link. In my case, my 540 had over 140K miles, and it was both the upper thrust arm bushings and the centerlink. I changed everything. I figure that leaving a weak link (old component) will just accelerate wear on the entire steering/suspension system.

Ramon
MBXB

Thread, come to life...

Was changing the upper thrust arm bushings and centerlink a costly exercise?

Thanks,

Rob
BobbyRitz

[MBXB]

It's been 2 yrs, but I replaced both upper and lower arms, the center link, idler arm, front wheel bearings and sway bar bushings. All Lemforder when it was applicable. Check BMA for prices.
It would certainly have been a lot more expense if I had taken it to an indy or the stealer.
The info on this board made the DIY job straightforward.