Besides balance, heavier tires and wheels (heavier than 14" OEM) tend to find weaknesses in everything in the front end.

The UPPER control (thrust) arm bushings are usually the culpret, not the lower control arm, and OEM e28 bushings seldom can control heavier tire imbalance or warped rotor syndrome. Use polyurethane.

Bob

Hi Gang,

I wanted to get your valued opinions on how to problem solve around a shimmy that I can't seem to isolate. I figure it MUST be the new Kumho Ecsta Supra 712s 225/50/16 on e28 M5 wheels. I had my installed re-check the balance for eachtire. But, he did NOT rebalance them for me OR break the seal on the rims. My installer stated that the "tires are in balance and the weights (glue on type not hammer on type) are in the correct place." Someone on the board has previously suggested that I take the car to an installer who has the FANCY Hunter Spin Balance machine (forget the model #). I have located one here in town and may go that route once I reach the 5k mark on the tires...still at about 2,500 miles, yet. I feel the shimmy especially when the car is cold but also feel it in the seat of my pants now even when the car is warm and the temp is well over 85F.

I mentioned this last time I was complaining about my shimmy but thought I tell you what is new. The lower control arm bushing are new, new biltein HDs (rear), front biltein HDs are from 95k (now sitting at 155k), PO installed some new front end goodies around 100k including center track rod. Are the other compoenents in the front end that I should be checking out more thoroghly?

I really feel the shimmy is in the tires and need further convincing. Is it worth the $60 seal broken turned on the rim a bit and rebalanced on the fancier Hunter machine?

However, I can also feel my that my driveshaft is getting sloppier. Also, the Guibo Disc was new at 145k...driveshaft had checked out as OK then.
Maybe I'm feeling some of that in the "shimmy" I'm reporting here. I know my rear differential mount (RDM)is also dried and cracking. Could that contribute the shimmy and be translated to the tires and the seat of my pants?

Ug! This is a pain. I appreciate your ideas/suggestions...even if they are repeated ones. I'm just stubborn.

Best regards,
Tim in N FL
87 535is
155k
CCA 185422