Front End Shimmy

[aviator]

I read everything on the 94 325is shimmy that is in the E30 section of your web site, but didn't really conclude if the gentlemen ever found the root of his shimmy. I am the original owner of an 89 M3 with 104kmiles. The front end is original and has never been serviced. My shimmy comes in from 60-80mph, and is somewhat dependent upon the smoothness of the road. When I'm travelling ~>80mph it goes away. Rotors are fine since stepping on the brakes at ~75mph doesn't create shakes. My rack leaks into the dust boot, but I monitor its' associated reservoir, and drain the boot so it won't rip from too much fluid in it (the original dust boot riped from being over filled, and that's how I knew my rack leaked because one day it burst and someone pointed out all the power steering fluid on the ground). Anyway, I guess I can jack up the car and start looking at all the bushings and use somekind of long breaker bar to see if any of the tierods wiggle abnormally, and try to shake the wheel when it is unloaded to see if I get wobble, but I believe I tryed the tire wobble routine once when it was jacked up not too long ago without any conclusion. What would you gentlemen suggest as the first thing to focus in on.

[Jeron]

Check you suspension and bushings as best you can but then concentrate on tires and wheels. Get them balanced, rotate them, try putting the spare on in front, check for uneven tread wear. Are the wheels factory or aftermarket? Cheap aftermarket wheels or damaged wheels may not be true and it wont show during balancing. The best thing would be to swap in a set of wheels you know to be good.

[aviator]

This is only the second set of tires I've had on the car. The rims are 15" originals from BMW and this second set of tires are the exact same size as the originals. The fronts look to be wearing evenly. The rears have worn in the center (probably due to over inflation). When I put the new set of tires on some 40kmiles ago, they were balanced, and alignment was checked all around and adjusted if needed. I wear my tires quite thoroughly, and the original set never created a shimmy when they were thoroughly worn. I did forget to mention that around the time that the tires were replaced, I did notice a pull to the right so even though a new set of tires didn't take away the pull, even once camber was adjusted, I had a right front camber compensator installed (factory bought), which is that 5" round thing that presses onto the shock and bolts to the shock tower, and it helped change the camber some 3 degrees (I have to check my notes), which helped minimize the pull, but didn't really eliminate the pull entirely, so I just left it in.

[Jeron]

If it has been 40k since you purchased tires, had them balanced and had an alignment then I stand by my original suggestion and I'll also add that you might need an alignment.