How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Robert Your Own Question
Robert, BMW Technician
Category: BMW
Satisfied Customers: 4716
Experience:  Fully qualified 19+yrs exp/self employed technician in the UK
Type Your BMW Question Here...
Robert is online now

BREAK JUDDER I purchased a BMW 320 series coupe (E92) on

This answer was rated:


I purchased a BMW 320 series coupe (E92) on 21 FebruAry 2014 from Evans Halshaw Plymouth. The car was originally purchased through a motability scheme via Stratstone BMW Hull. The car was first serviced by the dealer on 7/12/2012 with a recorded mileage of 18007. The same dealer carried out the MOT on 26/11/2013 with the odometer reading 25700. Before purchasing the car I road tested the car for a very short distance in slow moving traffic. On my return journey to Swansea I experienced some break judder. Can you advise as to what the problem might be?




Hopefully i can help..


Brake judder can in most cases be cause by issue with the brake discs/surface so to speak causing a pulsing of the brake pedal - tyres wouldnt really cause an issue like this - often cause for that can be an issue with the hydraulic side of the braking system causing the disc or discs to become warped and thus having warped discs and pressing on the brake pedal at speed you will feel that through the pedal/steering the disc run out should be measured with a dial gauge to see if thats the case or not..another cause for judder can be due to whats termed as Disc Thickness Variation which in term means the outside and inside of your disc surfaces are no longer parallel, so your cars pads are pushed into the thinner areas and kicked back out by the thicker areas. The movement is transmitted back through the caliper pistons up brake fluid to the pedal and you feel the judder in the really the next port of call really would be the disc's/surface condition wise..I do hope this helps..

Customer: replied 4 years ago.
Given the odometer reading at the MOT and the 700 miles driven to the date of purchase should this problem have been detected at its MOT. This was not referred to in Advisory items on the certificate

Hi..there thank for your reply..


If the brake judder only happens under speed say..depending on the severity of the judder you get then it may not of been picked during brake testing.sometimes although depending how good their brake tester is can pick up that..if the warp is slight on which ever disc is at fault and can only really be felt at speed under braking - only proper measurments dial guage for run out would see that.thats something that would need to be checked other reason could be lack of use.if a cars sits for period of time unused sometimes this can cause the surface of the disc to form a light surface rust as such.but wont form under the pads obviously when the car is used you will have the spot on the disc surface where the pads was against felt through the pedal.that too can in some case can cause judder.that might not be the case of yours but it would certainly be worth have the disc run out checked and see if indeed one of the disc is running out..I do hope this helps

Robert and other BMW Specialists are ready to help you