Getting crazy with brakes vibration

riccfrago · 10-15-2023, 11:34 AM

Hi everyone, I'm new on this forum and I'm writing here for a problem that afflicts my F22 MSport (2016, 90.000 km) for 6 months. Everything started after I hit a big road bump that i didn't see at about 50kmh so my car bounced over it bending the two rear wheels.
Car was undriveable for the vibratons, and after I fixed my 2 rims it's back as before. After 5-6 month from the incident, my brakes started to vibrate strangely. When I start the car, the first braking are ok, after that it starts to vibrate and I feel the vibration only on the seat, no steering or pedal vibration, for this reason is hard to define if the problem is on the front or rear. The feeling is like a warped wheel, but only when applying the brake. I checked the rotors runout and it's ok (under 0.1mm), and there doesn't appear to be a locked caliper piston.
Also, the vibration is strong and worrying if I do a soft brake in the highway, but if I apply more force on the pedal it seems to disappear.
I replaced and bled the brake fluid and I already changed 2 times my rotors spending lot of moneys, but the problem comes out after about 500 miles, so I'm getting crazy!!

.
A part this problem, I also notice a little vibration on my seat when I'm going on highway from 120 to 140kmh, more evident on downhill road, like an unbalanced wheel. Believe me, I checked my wheel balancing in 5 tire shops and everyone told me that my wheels are perfect.
I checked all the steering and suspension arms and also the wheel bearings and there's no play. The only suspect is on the control arm, I know it causes symptoms like mine. Even if moving the control arm by hand i don't feel any play, moving the wheel it seems to be there a little 'flabby', as on the attached video.
Please help me telling if you ever rescountred a similiar problem, and if based on your experience, this wheel play is normal or not.
Thanks a lot, have a nice day!

I share iCloud links because it exceeds size limit:
https://share.icloud.com/photos/05b5...W1MuffFAVLWQlQ
https://share.icloud.com/photos/030p...skm_XzXUHu30UA
https://share.icloud.com/photos/003j...iLTTH1-PIZqKjw

jb-slow · 10-16-2023, 07:02 PM

Is the other side tighter or the same?

riccfrago · 10-16-2023, 07:11 PM

Hard to say with precision, maybe seems a little tighter but there’s not so much difference.

marcthedark · 10-23-2023, 02:56 PM

Hunter Roadforce balanced?

riccfrago · 10-24-2023, 05:17 AM

No at the moment, I don't know any tire dealers with that equipment near where I live. I'll try to make a round of calls to find someone who has that type of balancer, perhaps in the BMW garage?
Any thoughts about the brakes? Is it possible that they only deform when hot?

10-15-2023, 11:34 AM	#1
riccfrago Registered 0 Rep 3 Posts Drives: BMW F22 MSport Join Date: Oct 2023 Location: Italy iTrader: (0)	Getting crazy with brakes vibration Hi everyone, I'm new on this forum and I'm writing here for a problem that afflicts my F22 MSport (2016, 90.000 km) for 6 months. Everything started after I hit a big road bump that i didn't see at about 50kmh so my car bounced over it bending the two rear wheels. Car was undriveable for the vibratons, and after I fixed my 2 rims it's back as before. After 5-6 month from the incident, my brakes started to vibrate strangely. When I start the car, the first braking are ok, after that it starts to vibrate and I feel the vibration only on the seat, no steering or pedal vibration, for this reason is hard to define if the problem is on the front or rear. The feeling is like a warped wheel, but only when applying the brake. I checked the rotors runout and it's ok (under 0.1mm), and there doesn't appear to be a locked caliper piston. Also, the vibration is strong and worrying if I do a soft brake in the highway, but if I apply more force on the pedal it seems to disappear. I replaced and bled the brake fluid and I already changed 2 times my rotors spending lot of moneys, but the problem comes out after about 500 miles, so I'm getting crazy!! . A part this problem, I also notice a little vibration on my seat when I'm going on highway from 120 to 140kmh, more evident on downhill road, like an unbalanced wheel. Believe me, I checked my wheel balancing in 5 tire shops and everyone told me that my wheels are perfect. I checked all the steering and suspension arms and also the wheel bearings and there's no play. The only suspect is on the control arm, I know it causes symptoms like mine. Even if moving the control arm by hand i don't feel any play, moving the wheel it seems to be there a little 'flabby', as on the attached video. Please help me telling if you ever rescountred a similiar problem, and if based on your experience, this wheel play is normal or not. Thanks a lot, have a nice day! I share iCloud links because it exceeds size limit: https://share.icloud.com/photos/05b5...W1MuffFAVLWQlQ https://share.icloud.com/photos/030p...skm_XzXUHu30UA https://share.icloud.com/photos/003j...iLTTH1-PIZqKjw
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10-16-2023, 07:02 PM	#2
jb-slow First Lieutenant 111 Rep 338 Posts Drives: m235i Join Date: Mar 2019 Location: puyallup iTrader: (0)	Is the other side tighter or the same?
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10-16-2023, 07:11 PM	#3
riccfrago Registered 0 Rep 3 Posts Drives: BMW F22 MSport Join Date: Oct 2023 Location: Italy iTrader: (0)	Hard to say with precision, maybe seems a little tighter but there’s not so much difference.
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10-23-2023, 02:56 PM	#4
marcthedark Lieutenant 120 Rep 410 Posts Drives: M240i xdrive Convertible Join Date: Apr 2017 Location: Phoenix Metro Area iTrader: (0)	Hunter Roadforce balanced?
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10-24-2023, 05:17 AM	#5
riccfrago Registered 0 Rep 3 Posts Drives: BMW F22 MSport Join Date: Oct 2023 Location: Italy iTrader: (0)	No at the moment, I don't know any tire dealers with that equipment near where I live. I'll try to make a round of calls to find someone who has that type of balancer, perhaps in the BMW garage? Any thoughts about the brakes? Is it possible that they only deform when hot?
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