MINI Cooper Forum banner

Rear Knocking Noise

21K views 8 replies 4 participants last post by  ProjectPride90 
#1 ·
Got a weird knocking/clunking noise coming from the rear. Only seems to occur at 30mph or less and goes away when applying the brakes or putting the handbrake on one notch. As soon as I release the handbrake, the noise is back.

Changed the rear anti roll bar bushes last week just because they were cheap and thought it was worth a go, but doesn't seem to have been the cause of the noise. Its still there!

Logic would make me think that if the noise goes when applying brake pressure, its a loose caliper/brake pad or similar. Had the caliper off last weekend but couldn't see anything that looked out of the ordinary. Didn't want to apply the brake pedal to see if the caliper moved as I didn't have a tool to wind the piston back in. I've ordered one now and have Friday off work to have another look at this. This noise is fast becoming my nemesis!

Has anyone had this before and what cured it for them?

Thanks
 
#2 ·
Hi ya

It could be brake related for shore check the slider bushing and the rubbers make shore where the hand brake fits to the caliper us free to move they do seize in and can cause a rattle.
Failing they check you exhaust mounting brackets they rot away at the top and then touch the body. Item 11

http://www.realoem.com/bmw/showparts.do?model=RE32&mospid=48020&btnr=18_0489&hg=18&fg=20


If not check out you cross braces from your sub from to wheel hub.
The shock absorber top bushes do wear
 
#3 ·
Update so far.....
Universal caliper tool turned up yesterday so had the caliper off again today. Wound the piston in, this went in fine, not seized thankfully. Was a bit worried it may have been a seized caliper, but thought it wasn't because the handbrake worked fine on that wheel.
Cleaned off all the build of of brake dust and a little corrosion that was on the clip that holds one of the pads on the piston. There was no copper slip on either of the pads so put some on. Then also put some silicon grease on the slider pins. Put it all back together and so far so good. Hopefully that is, just needed a good clean and re-lubricating.
Before, I could drive literally 100m down the road and the noise was there. Did a couple of miles round the block and no noise so fingers crossed thats it.
Got a 200 mile round trip to Bristol this weekend, that will test it!
 
#4 ·
Spoke too soon I think, went for a longer drive, knocking is back. Had a feel of the brake discs/rotors and one of them is hot to the touch. One side isn't really hot but the other side where the knocking noise is coming from is really hot after driving.
I don't think the caliper is seized as the piston wound in fine when I took it apart earlier.

Could it be the handbrake isn't releasing fully? Jacked up, I can spin the wheel ok, but I wonder if after using the handbrake a couple of times, its just not releasing fully causing the disc to heat up a bit.
 
#5 ·
Hi ya

Make shore where your hand brake cable goes in to the calliper its free to move or it will cause the calliper no to sit square and to drag causing the pad and disk to over heat. I always remove mine and clean the up and re grease them. It's a known place for corrosion and can be a real pain to free off I had one I had to cut the cable off and drill and ream out the hole on the calliper.
Also check you calliper brackets are not bent as some people do not realise you have to wined the piston back in they try to leaver it in with a big GS screwie damaging the mounting

This may help

http://www.mini2.com/forum/maintena...erate-handbrake-cable-rear-brake-caliper.html

Hope this helps
 
#6 ·
Thought I would update on the issue, that now seems to be fixed!! Driven a fair few miles over the past couple of weekends and the horrible knocking has not come back after the latest trial fix.

Cure = new caliper spring clip. About £5 from the main dealer. Old one fitted fine, but was relatively easy to take off and put back on with a screwdriver prying it out. When comparing the old one to the new one, the old was slightly out of shape, not a lot, but a little. But fitting the new one was a lot more of a struggle. The tension was far more than the old. Anyway, seems to have done the job.

Kind of make sense when I google caliper spring clips to see they are also known as anti rattle clips! Doh! Should really have been the first thing I looked at. Oh well you live and learn.
 
#7 ·
Got a weird knocking/clunking noise coming from the rear. Only seems to occur at 30mph or less and goes away when applying the brakes or putting the handbrake on one notch. As soon as I release the handbrake, the noise is back.

Changed the rear anti roll bar bushes last week just because they were cheap and thought it was worth a go, but doesn't seem to have been the cause of the noise. Its still there!

Logic would make me think that if the noise goes when applying brake pressure, its a loose caliper/brake pad or similar. Had the caliper off last weekend but couldn't see anything that looked out of the ordinary. Didn't want to apply the brake pedal to see if the caliper moved as I didn't have a tool to wind the piston back in. I've ordered one now and have Friday off work to have another look at this. This noise is fast becoming my nemesis!

Has anyone had this before and what cured it for them?

Thanks
I HAD a rattling light knocking noise making me crazy from the rear of car I changed the sway bar bushes and no luck ,I decided in my mind it’s gotta be the upper shock bushings ,then upon inspection after removing rear wheel I could see the bushing on one side was almost non existent ,after changing both shock bushings noise is now long gone .....
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top