Problem with rear brake disc/pads?

Hi all…
As per my pic here really. Clues as to what can cause this?

Tia👍

This looks to be a bit of an issue on mk3s from what I’ve seen. Mine had uneven wear on the rear too but it’s mainly the outside that seems to be affected as the inside 8s driven directly off the piston. Removing and refitting the pads and making sure the ears have a little bit of grease on them to move freely in the guides and make sure the slider pins aren’t sticking. Mine was cured after I did new pins and shims evident from the now even wear on my new discs and pads.

Looks like worn pad and metal to metal.

New pads and discs only 5k miles ago.

The good news is that you’ve got a decent shine on your wheel nuts :+1:

Thank you😂

Sticky caliper?

I would remove the caliper and check that there is nothing stuck between pad and caliper that is twisting the pad very slightly.

That was the same on my NC3.75 when I got it.
As you already have new discs/pads….
Take the pads out.
Fully clean and regrease the slider pins (check and inspect) with the correct red grease.
Make sure you don’t mix them up as they are slightly different. (That’s if they were put back correctly of course).
Make sure the piston is fully rewound properly.
If you don’t know they have to be turned and pushed back.
If you just try pushing them you will damage the caliper.

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I had the same on my daily driver, couldn’t find out why there was an unswept area on the outer part of the disc on one side only.
Anyways new discs and pads sorted it, doesn’t help I know being as you’ve only recently renewed them.

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Last week I took my Mk2 into the local tyre depot for two more new tyres. Basically the existing tyres had ‘died’ of old age and although had lots of tread left, for peace of mind I have changed all four now. Whilst they they pointed out that the rear pads were getting very low so after getting a set fof EBC Ultimax DP1003 from MX5parts eI began the job this afteroon. Problems? Well two of the pads have tiny metal clips attached to them and I’ve no idea what they are for. Nothing with the pads nor in the workshop manual. Accessibility is poor on my drive, half of which is on a slope, the other half is narrow. After years of stirling work the trolly jack has let me down and fails to pump up. I used the car jack instead but that wasn’t really man enough to lift the entire rear of the car. Accessibility around the rear hubs was really difficult and I had to cut away some of the rubber around the bottom M10 bolt to get purchase on it. With everything cleaned up and lubricated, it all went back well enough although I’ve since noticed that the old pads had shims clipped to them. I’m of two minds whether or not to take these off, clean them up and refit them. I’ve never before seen pads with shims like these. So after a few hours of irritating work I’ve struggled to get one corner done and am now wondering whether to take one side off and refit the shims…and what about those tiny riveted on clips?

’ those tiny riveted on clips? ’

Pad wear indicators , make a squealing noise when the pad wear allows them to contact the rotor. Maybe.

Ebc give you the wear indicator clips seperate to clip on yourself. I didn’t bother fitting them as I check my brake pad wear often enough to see when they’ll need changing.

Ah thanks, I’ve not heard about those before. My manual says that the shims should be swooped over onto the new pads. Really? Are they really necessary?

Some pads come with bonded shims in place of the factory shims. Obviously the stainless slide inserts need to be reused. My ebc pads had the bonded shims, this meant that the factory shims couldn’t be used over the top. I did have the info from ebc somewhere that said they aren’t required but I can’t remember where it was I found it.

You can see them installed in this pic.


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Wipe it down with phosphoric acid and give it a bit more time to bed in.

Rear discs are always a problem if the brakes are not used hard at times.

Check the slide pins and put red rubber grease on them NOTHING ELSE!

Yes,last week I took the caliper off,took the pads out and also the slider pins. Gave all parts a good clean off,re greased all necessary parts including the slider pins( prior to this they were nice n free).
However,all this doesn’t seem to have cured the problem,as after I have driven the car for quite far enough to see some difference on the disc,it doesn’t look very much different🤦

Greased, with what?

I used a smidgeon of CopperSlip as I’ve always done.