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View Full Version : I'm at a loss here! Replaced everything and still 60mph shimmy!!!



RenaissanceMan
07-29-2009, 10:17 PM
Folks, I need some serious guidance here. I have been contending with the 60mph shimmy on my '95 525it almost as long as I've had the car.

Today I took on the task of installing new Bilstein HD struts and brand new Lemforder thrust arms (which had M5 bushings pre-installed, as I was told they'd be the most heavy-duty). We just took the car for a ride, and dangit the shimmy is STILL there. The car rides much tighter, but that infamous shaking at highway speeds has not gone away.

Let me tell you what else I have done to try and solve this problem:

-Replaced all 4 wheels with new ones
-Replaced all 4 tires with new ones
-Tightened up the steering box to eliminate play

FWIW, I have not yet replaced the control arms, but from what I have read, this is most often caused by the thrust arm bushings, instead. Is that correct?

What the heck else could be causing this to continue? I'm about to tear my hair out, as I've spent so much time and money trying to solve this issue. Any advice is GREATLY appreciated!

russiankid
07-29-2009, 11:13 PM
Check the transmission mounts and center bearing on the driveshaft. My car vibrates at 55mph because my transmission is not in great shape.

MBXB
07-29-2009, 11:31 PM
Steering tie rods, center link and idler all tight?

Scott C
07-30-2009, 05:50 AM
Did you tighten the big nut on the steering column (above your feet and above the panel on the bottom)? There was a LOT of freeplay between the steering wheel and steering box on my car - I had like two turns of this nut to tighten her up.

Scott

Dave M
07-30-2009, 06:57 AM
I second the tie rods. This and a good wheel balance fixed my shimmy.

Dave

genphreak
07-30-2009, 07:53 AM
1. Left field this; but some tyre places are dumb with our cars: Do the new wheels have the right hub diameter to seat perfectly on the hubs (maybe they just need hub-centric rings?)

... ( the cheapest solution so I said it up-front.)

2. I had the same poos with my 535 once (but only downhill under brakes), turned out to be the Lower Control Arm bushings.

3. However when the SLS in my 95 touring had the wrong fluid and a slipping serpentine belt, it also had a really weird 60mph shudder that I couldn't isolate (until I addressed the SLS) - the thing that gave this away was that it was made worse by weight in the back ;)

I've heard of rotors being able to cause the wobbles too...

Kibokojoe
07-30-2009, 11:16 AM
For me it was rotors. List everything you have done so far

Scott C
07-30-2009, 02:25 PM
Did you tighten the big nut on the steering column (above your feet and above the panel on the bottom)? There was a LOT of freeplay between the steering wheel and steering box on my car - I had like two turns of this nut to tighten her up.

Scott

Have you lifted the front end, and inspected by moving the wheel by hand vertically and laterally while someone holds the steering wheel?

Scott

Tiger
07-30-2009, 02:37 PM
What wheels do you have now?

In your case, I would have to guess the lower control arms are your problem.

632 Regal
07-30-2009, 09:36 PM
out of round tires

and everything they said

SnakeyesTx
07-30-2009, 10:46 PM
When you installed the new thrust arms, did you preload them with the weight of the car on the suspension before you tightened them down? Lots of shops just bolt them down in the air without putting the weight down on them and they crap out from almost immediately to within the first 5000 miles. That and check everything previously listed above.

Also... check the tires for a broken belt, usually easy to spot if its near the sidewalls as a bulge or an indentation.

Tiger
07-31-2009, 08:25 AM
Actually, I am worried about his wheels... if not the right size hub hole... and without the spacer... he will get that shimmy.

Preloading error will not give that shimmy problem but will do so later on... three different mechanics and all of my thrust arm bushings are shot within 7000 miles. So pissed that I will do my own this time around with M5 bushings.

632 Regal
08-02-2009, 12:59 AM
ditto, and also out of round tires.


Actually, I am worried about his wheels... if not the right size hub hole... and without the spacer... he will get that shimmy.

Preloading error will not give that shimmy problem but will do so later on... three different mechanics and all of my thrust arm bushings are shot within 7000 miles. So pissed that I will do my own this time around with M5 bushings.

sal_park
08-02-2009, 08:03 AM
-Replaced all 4 wheels with new ones

What wheels are they ? are they for an E39 and you're using them with hub ring adapters ? This setup on mine cause the shimmy which went away 100% after changing back to the original E34 alloys with no adapters.

hth

sal

leicesterboy15
08-02-2009, 05:00 PM
Actually, I am worried about his wheels... if not the right size hub hole... and without the spacer... he will get that shimmy.

Preloading error will not give that shimmy problem but will do so later on... three different mechanics and all of my thrust arm bushings are shot within 7000 miles. So pissed that I will do my own this time around with M5 bushings.

Same here too, I used 750i bushings last time and they are already gone in less than a year, I've got some powerflex ones with new arms now and will fit them when I get a chance.

As for the shimmy the only thing you haven't replaced is the lower control arms so that sounds like a good bet! But as others have said when I had the shimmy I got the wheels tracked and balanced with new tie rod ends and this made a big improvement although it didn't go completely until I replaced the upper and lower arms. Either that or the upper arms were not fitted properly which is easy to do.