Squeeling from brakes after disks & pads replaced

Squeeling from brakes after disks & pads replaced

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Discussion

MitchT

Original Poster:

16,004 posts

212 months

Saturday 22nd June
quotequote all
BMW 120d - E87 - Feb 2005 - 102k miles

Rear risks and pads were replaced in March when it had its MOT. Since they they've been squeeling at low speed, notably when NOT braking. You set off and the noise starts and then goes way as the speed builds up. I'm putting it down to the new disks and pads needing to bed-in, but my research suggests that this happens when braking. In my case it happens when not braking. The noise went away a while after the work was done but has returned in the last couple of days. Maybe the hot weather has caused everything to expand and closed the clearances that had built up as the parts bedded-in... or maybe it's something else.

stevieturbo

17,335 posts

250 months

Saturday 22nd June
quotequote all
You'd need to pull them apart, make sure pads etc are all free and not sticky, any anti-squeal shims are in place etc etc.


MitchT

Original Poster:

16,004 posts

212 months

Saturday 22nd June
quotequote all
I should point out that my knowledg of cars is limited to driving and checking tyres, fluids and bulbs. I won't be pulling anything apart myself! Just wondered if it needed to go to the garage or if it'll settle down by itself.

stevieturbo

17,335 posts

250 months

Saturday 22nd June
quotequote all

Dave Brand

930 posts

271 months

Thursday
quotequote all
Could be a characteristic of the new pads - known in the industry as "twitter".

Smint

1,802 posts

38 months

Get someone methodical to pull the pads.

Squeal is often high frequency vibration, sometimes the source of the noise can be seen as a very shiny spot of contact where the culprit has been moving minutely, this might be piston/pad backing plate contact or edge of backing plate where it locates in the caliper carrier.
Another source of squeal...if there's a thin metal plate behind the brake disc could it be bent or a stone trapped between it and disc.

Make sure any required shims or spring clips are present and in good condition, renew if corroded or weak, make sure pistons are moving freely in their bores by exercising them a few times, and any slide or locating pins are clean and lubed where necessary, before refitting the pads give everything a good clean up, not with brake cleaner spray alone but by old fashioned scraping and wire brushing, then before re-installing where there is metal to metal contact (ie piston to pad backing plate) a wipe with the pro's chosen lube should shut things up.

Not saying its the case here, but too many people seem to think brake replacement is a 2 minute job (so anyone doing the job properly and charging accordingly is ''ripping you off mate''), and yes it can be a 2 minuter if they miss all of the above out, proper brake refitting isn't a 2 minute job.