New Front Brakes - Shimmy after 1 month - why me?

late better than never

BMW et al don't recommend turning rotors for at least one simple reason: it's not worth the time spent by a mechanic (around here $100/hour) versus the cost of new rotors.

BMW has had major rotor warp issues before: E28 (second generation 5 series) including first gen M5 were famous for it. Back in the day, the smart money would go to the dealer, who was warranty-bound to replace "failures" (shimmies) within the first year. Basically, pay once, then replacement rotors every so many months until the dealer hit on a combination of rotors and pads that would last. It can be that you have something of the same issue here.

That said, it's certainly a good idea to have your front end bushings and suspension parts looked at. Also verify your rims are round (I have a bent rim if you need a match).

I have the misfortune to have owned an '83 533i and '87 735i, both of which had well-deserved bad reputations for front shimmy. I fixed the 533i by selling it. New owner put new tires on the 15 inch rims I sold with the car, and all was well. I'm stuck with the 735i, no one will buy, though I've got almost all the shimmy gone, it has other issues. See my post "Trouble in Zenith-land".

I'm not familiar with rotor or pad make you quote. I have used Balo rotors and Axxis (ex-PBR) Metal Master pads for almost 20 years on various bimmers of mine, without trouble. Some say they are slow to warm up, some that those pads are hard on rotors, but I find them adequate. Stock BMW pads make dust like fire makes smoke, only moreso. Ditto for the Textar pads on the wife's C280.
 
Shimmy problems--no one has suggested replacing another part

What is the condition of your lower control arms?

In the case of the 5 & 7 series front end problems lower control arm wear was a major cotributing factor--not so critical or key to the E-9--but when 35 years or so have gone by a change there will often help--

BLUMAX had his changed a couple of years back along with other suspension componentes and no shimmy here at 38 years of age--that is BLUMAX's age of course...... (;>)
 
Appreciate all the advice. Update to date is that I have had the suspension checked yesterday - all appears to be fine as I have had nearly all the components updated over a period of time. The only bushes that had minor marginal play where the caster but was advised this would not cause lateral shimmy through the wheel.
Wheels are round - had them restored recently and checked out fine. Bearings where replaced not long ago.
Have not checked the state of the calipers and will do so asap.
New pads and refinish of the rotors scheduled for Tuesday and I will bed the brakes in myself as per procedure (have not followed before).
Shimmy appears to be most noticeable on light braking right up to a rolling stop. On most occasions if I stomp on the brakes the shimmy is only very faint - probably useful to have mentioned this in original post...
The car drives beautifully in every other regard so the shimmy is a real pita
 
I only scanned over this string and did not see any mention of the possibility that the shimmy is being caused by a worn out steering stabilizer.
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... don't think coupes have steering stabilizers, do they? :?:
 
steering stabilizer

No 3.0CS, 2800CS, 635CSI, 533i, 2500, Bavaria, 735i, 528i, or any of my morethanadozen 2002s I owned, ever had a steering stabilizer. But y'know, I haven't seem 'em all...
 
Appreciate all the advice. Update to date is that I have had the suspension checked yesterday - all appears to be fine as I have had nearly all the components updated over a period of time. The only bushes that had minor marginal play where the caster but was advised this would not cause lateral shimmy through the wheel.
Wheels are round - had them restored recently and checked out fine. Bearings where replaced not long ago.
Have not checked the state of the calipers and will do so asap.
New pads and refinish of the rotors scheduled for Tuesday and I will bed the brakes in myself as per procedure (have not followed before).
Shimmy appears to be most noticeable on light braking right up to a rolling stop. On most occasions if I stomp on the brakes the shimmy is only very faint - probably useful to have mentioned this in original post...
The car drives beautifully in every other regard so the shimmy is a real pita
Click to expand...

I think with this valuable info you have all but eliminated the front suspension as the culprit. :wink:

Let us know what you find out after bedding the brakes.
 
Update:
Texta pads and Texta rotors fitted today but unfortunately after making the frivolous comment about the car running 'beautifully in every other regards' I managed to bust something in the driveline on the way to the mechanics yesterday. Lesson to all - don't tempt fate with unnecessary self congratulation :)
Now opinions please.
The driveline problem - took off 'fast' in 1st to approx 4300rpm into 2nd backup up to 4300rpm and bang clack clack clack - sounded like a shredded belt - which incidentally occurred at the same traffic lights not 3 weeks prior - no joke :roll:
Car is driveable but there is a shocking vibration in idle and at all speeds. When clutch is cold and I engage then the clack clack returns , vibration still present.
Car back on hoist tomorrow I suspect busted clutch or is there some other area to consider - bearings, weights - guess the mechanics will get to the bottom of it but a second(or more) opinion is valuable to me to help understand potential causes.
Failing that the car is booked in to the local chapel for an exorcism over the weekend. No offence to anyone intended
 
Update:
Texta pads and Texta rotors fitted today but unfortunately after making the frivolous comment about the car running 'beautifully in every other regards' I managed to bust something in the driveline on the way to the mechanics yesterday. Lesson to all - don't tempt fate with unnecessary self congratulation :)
Now opinions please.
The driveline problem - took off 'fast' in 1st to approx 4300rpm into 2nd backup up to 4300rpm and bang clack clack clack - sounded like a shredded belt - which incidentally occurred at the same traffic lights not 3 weeks prior - no joke :roll:
Car is driveable but there is a shocking vibration in idle and at all speeds. When clutch is cold and I engage then the clack clack returns , vibration still present.
Car back on hoist tomorrow I suspect busted clutch or is there some other area to consider - bearings, weights - guess the mechanics will get to the bottom of it but a second(or more) opinion is valuable to me to help understand potential causes.
Failing that the car is booked in to the local chapel for an exorcism over the weekend. No offence to anyone intended
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Sorry to hear. Before the calamity did the shimmy go away after the new pads and rotors?
 
Hi - shimmy is not apparent at the moment - bedded the brakes in as per process last night. Shimmy will normally appear 1 month or so after replacement so fingers crossed.
Car on hoist today - mechanics suspect broken straps in the pressure plate causing the vibration and noise from the latest event- to be confirmed.
 
Tony,
Hope you found your latest problem - sorry to hear about your woes.
I did have more thoughts about you braking problem after a month.
As you have eliminated everything else but if it occurs again after a month I would like to throw out the following thoughts...

1.. Calipers lined up and true to the disks?
2.. Piston or pistons sticking slightly, the pads are still slightly touching the disks.
3.. If 2 then the disks will heat and start to warp.
4.. Master cylinder piston is not coming all the way back to the rest positon.
5.. Flex hoses are the old? if so they are beginning to swell internally restricting fluid movement.
6.. pedal rod to master cylinder adjusted correctly?

Hopefully you will not have the problem again so 1 to 6 do not apply!
Malc
 
Car is now back and as suspected a busted strap on the pressure plate..either due to eventual wear and tear or an extremely dodgy gear change by yours truly..both a distinct possiblity.
Car and gear change are now much lighter in feel - but this could be due to the decrease in the weight of my wallet..not sure.
Brakes appear to be fine at this point although the Texta components certainly appear to throw out more dust than previous brands used.
Will monitor and advise if/when shimmy returns and have noted the other areas to investigate.
Appreciate all advice to date.
 
Car is now back and as suspected a busted strap on the pressure plate..either due to eventual wear and tear or an extremely dodgy gear change by yours truly..both a distinct possiblity.
Car and gear change are now much lighter in feel - but this could be due to the decrease in the weight of my wallet..not sure.
Brakes appear to be fine at this point although the Texta components certainly appear to throw out more dust than previous brands used.
Will monitor and advise if/when shimmy returns and have noted the other areas to investigate.
Appreciate all advice to date.
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Well, I think you already eliminated the front suspension and any of the other problems suggested here. For if it were one of those items it would still shimmy after you had replaced the new pads and rotors.
 
What‘s to understand? It is about sharing knowledge and experience to help each other out. What I don’t understand is the arrogance of your post! This forum is to help people not lambaste other members because you think you have the only correct answer to someone’s problem. My experience was identical to his except it was a different BMW. How does that relate to a coupe? I don’t know how many BMW’s you have been under but suspension is very similar on all of them, they just keep improving their basic design. I had a shimmy during braking on my 535i so I also assumed the rotors were warped. I replace rotors and pads and guess what, about a month later the shimmy returned. It turned out to be the control arm bushings were worn out. I replaced the all the bushings, ball joints rotors and pads and never had the problem again. So does “And from the OP's original post he is having this problem "only when braking" which would probably rule out a suspension issue” this problem must only apply to the coupe suspension? Doesn’t it make sense to you that if the bushings are worn there is excessive slop in the front end and applying the breaks would cause a shift in the location of the control arm starting a vibration in the front end? MichaelP suggested the same thing as I did, maybe he knows something too?

I’ve been on this forum long before it migrated over from Road Fly the intent has always been help each other out with information not chastise people. It is because of my past experience I’m 90% certain it is the suspension and not “pad bedding” yet I didn’t write a nasty post lambasting you four your suggestion did I? In general our posts should be limited to helpful advice and the arrogance should be left out. This poor guy has done his brakes twice now maybe it is time to consider other possibilities besides the pads?

Ummm,

Scott
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Ummm, I think we have already eliminated the front suspension as an issue.
 
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