stumped on 50-60mph shimmy

[TimGinCentralNJ]

...adding the slightest resistance to just one of your front wheels is enough to alter your suspension geometry, 'bringing to light' even the slightest amount of play in the form of a shimmy. I'd never have believed it either had I not been through it myself

All I'm saying is, if you've checked/repl'd everything else, do yourself a favor and check out your calipers to ensure they're releasing. Look for unevenly worn or unevenly "hot" rotors up front, and just make sure both front wheels spin freely. It's a cheap test, and one often overlooked IMHO.

Tim G.

so a shimmy could also be caused by the brakes? (if the suspension turns out to be ok)

[MBXB]

JP,

Bad brake rotors can cause shimmy.
I had a new but not balanced rotor drive me and my tech nuts.
He didn't believe me at first. Got a free replacement.

Ramon

so a shimmy could also be caused by the brakes? (if the suspension turns out to be ok)

[jplacson]

Thanks! I also want to mention that I have a rear "clunk" when cornering. I'm trying to see if my shimmy might be tied into this as well... what could cause the clunk? Rear shocks? Or the subframe bushings/mounts? This only happens while cornering, not accelerating.

[sonar5]

Hi Folks,

I read through this thread with interest.

You may be looking past one thing that was the problem with mine. I recently had my front brake pads replaced and rotors, (rears were fine), and still had the 55mph deceleration shake.

Was going to get it balanced, and Guess what it was. Nothing to do with the front end.

It was the CENTER BEARING, which attaches to the driveshaft..... Torn to shreds. My ace neighbor mechanic sent me the pics of it, and it was trashed.

$34.50 at pelican parts. He let's me get the parts and he fixes the car for me at his shop in San Diego.

Here is the link for the part:
http://www.pelicanparts.com/bmw/cata...tranny_pg3.htm

Here is a procedure I gave to him, even though mine is an automatic, the guy at this site did it with lowering and NOT removing the whole exhaust.

http://www.bmwe34.net/e34main/Mainte...terBearing.htm

So take a look at that, and I will be willing to guess that may be the problem. remember a lot of mechanics love replacing every single shimmy front end piece, and never look past that. Tell your mechanic to think outside the box.

Best of Luck,
Joe


1994 525I (Current)
1987 325 (Sold in 2003)
1994 525I (Sold in 1996)

[David]

I've been battling the same thing for a year. I had one part that helped - one of my Pirelli tires would deform when it got warm, so that got replaced. That took away some of the problem, but I still have the vibration. All tires are balanced, wheels are brand new.

Ok, I've changed my bushings, stab links, front shocks, and had my wheels aligned already.

Now the 50-60mph shimmy is back. Although above or below this speed, no vibrations at all.

What else could be wrong? A few E34 owners here in the Phil say that this is really the problem with the E34.

Could the Thrust arm itself be the problem, and not just the bushing? Could the lower control arms also cause this?

[jplacson]

Is this the same as the flex disc/propeller coupling? if so, I had mine changed already.

[Javier]

normally it is clever to switch them both together. You probably did.

[Jr ///M5]

Yup, Lemforder is the brand to stay with on suspension parts. There is one thing I can't believe you guys haven't suggested....tire balance. It is probably the cheapest and easiest fix for the biggest majority of the shimmys.
George's attitude toward the suspension woes is the best. If you can afford it, replace everything that's under there, while you're there. You'll enjoy your shimmy free ride over and over without regrets...that is, unless you skip the basic tire balance issue..=)

Jr

[632 Regal]

shimmy until its replaced with a round tire. I have been dealing with this crap since I got my tires at Discount tire scammers, almost a year now. They DO NOT want to honor a defective tire issue because the square tires are within spec. what spec is beyond me. All I know is I replaced everything and it's tight, at a slow crawl the car shakes back and forth side to side, which to me is a bent rim or a good for **** tire, well it aint a rim and the tires within spec so... withoud an AK and a mask I'm blessed with discount tires warranty till I burn the tires to the cords.

Can anyone tell I was there again yesterday wasting 3 hours trying to get this issue taken care of again? Total time must be pushing 15 hours so far...they are nice guys and all, I want to invite them to an ally in detroit and congratilate them on their fine service.

Within spec.

I was readin (dont i always) that tires from Florida are better tires all around cause of the freeway heat and the blems get sent to the other states, anyone hear about this or am I just dreamin about round tires?

[MO525]

Yup can use aluminum in cars whether they came with them on not. Most don't...I don't for example. Pretty much the only difference is weight...and not proportionate to the density diff between aluminum and steel as aluminum has a lower yield strength so has to be actually larger than the steel arm (more volume/section modulus) to compensate which erodes some of the weight savings.
Think you made the right choice with steel :-)...believe even the most discerning could never tell the difference on the street or track.
HTH,
George

A previous owner must have installed them.
I didn't even think about it until this thread brought up the subject.
Mine still have the remains of the part number tag/tape on them.
As long as they work properly, I don't mind if they're steel or aluminum.