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Hello clever folk,

does anyone have any experience with brake binding issues? When cold the car is fine, but when it gets to temperature the nearside front wheel is binding. I cannot feel it pulling to one side but the wheel gets hot compared to the other side.

I have been googling and found a minefield of possibilities. I have standard OEM brakes with original brake pipes. The discs and pads seem fine and plenty of life left in them.

Any tips would be very much appreciated as it's going up on axle stands this weekend

Have this on mine. After doing some research turns out most people who had the same, it was a sticking piston and that they either replaced the caliper or used a rebuild kit. I purchased an old set off a forum member, have sent them to Bigg Red who powdercoat and replace the pistons, seals, bleeds screws etc with new and send them back. Once they send them back I’ll be getting them put on and at the same time new discs and pads and bearings on the front may even get some backing plates new at the same time. Won’t be pipes on mine as the previous owner replaced all the lines in 2014 and I replace the fluid every two years and have replaced the flexible lines with Goodridge braided hoses.
When I have had the work done I’ll have all four calipers spare and will either get them refurbed and sell them or sell them as they are.

As above, fairly common issue. I've not had it (yet) but know a few that have.

Had it on mine, and it got so hot that it increased the tyre pressure enough to trigger the pressure warning - and it started to slightly pull the car to the left.

Drove it slowly to the closest dealer, and a couple of hours later the called to quote me the cost to replace a pair of calipers, pads & discs (as it's a safety issue, sir).

Went to pick it up a couple of days later and noticed that the discs where the original ones, and asked why...only to be told that BMW Warranty would only pay out for the actual broken parts and not anything else - then they asked me to pay for the new set of pads they had to fit - and wondered why I bit their heads off!

mmm-five wrote: ↑Tue Feb 12, 2019 2:40 pm Had it on mine, and it got so hot that it increased the tyre pressure enough to trigger the pressure warning - and it started to slightly pull the car to the left.

I had this on mine, though i don't believe it's the tyre pressure that's affected. The tyre pressure is judged via the ABS sensors (wheel speed etc) so i believe the binding brake interferes with this element as one wheel will be trying to rotate more slowly.

Darkangelv2 wrote: ↑Tue Feb 12, 2019 2:47 pm

mmm-five wrote: ↑Tue Feb 12, 2019 2:40 pm Had it on mine, and it got so hot that it increased the tyre pressure enough to trigger the pressure warning - and it started to slightly pull the car to the left.

I had this on mine, though i don't believe it's the tyre pressure that's affected. The tyre pressure is judged via the ABS sensors (wheel speed etc) so i believe the binding brake interferes with this element as one wheel will be trying to rotate more slowly.

It won't be rotating slower though! Even if there is slight binding, in a straight line both wheels will be rotating exactly the same number of times...assuming the wheel is not locked & simply scrubbing the tyre along the road.

Sticking caliper heats up disc, which transfer heat to wheel, which transfers heat to tyre.

Hotter tyre = higher pressure = bigger circumference = less rotations = pressure warning light (mine was 6psi over when checked at the side of the road).

Darkangelv2 wrote: ↑Tue Feb 12, 2019 2:47 pm I had this on mine, though i don't believe it's the tyre pressure that's affected. The tyre pressure is judged via the ABS sensors (wheel speed etc) so i believe the binding brake interferes with this element as one wheel will be trying to rotate more slowly.

It may be trying to rotate more slowly but it's not likely to succeed without a trail of tyre rubber in it's wake! I think the point is that the binding brake makes the wheel run hotter which expands the air inside the tyre and causes the overall diameter of the tyre to increase slightly. The TPS looks at the speed difference between each wheel and because one is slightly larger it runs at a different speed and hence fires the warning.

^^^^bah, beat me to it!

I had this on mine a few weeks ago. I bought new pads as the old ones where old and knackered.

Stripped the calliper down whilst still attached to the car, and pushed the piston out fully with pads removed.

Bought Red brake calliper geese online and cleaned and oiled the locator pins and piston.

Then pushed piston all the way back in and reassembled and put on new pads.

The brake has been fine since

Yup happened to mine too, as with mmm-five my tyre pressure warning went off. Also, horrible juddering under braking. I got a refurbed one from eBay for £150 IIRC, had to send my old one back to them. Word of warning though, I think most refurbs come silver even if the picture is black... so if you can spare the time to paint and lacquer it, it will be worth it. I couldn’t as the car is a DD and my OCD was disturbed for at least a year before I got round to painting it

captainmorgan999 wrote: ↑Tue Feb 12, 2019 1:51 pm Hello clever folk,

does anyone have any experience with brake binding issues? When cold the car is fine, but when it gets to temperature the nearside front wheel is binding. I cannot feel it pulling to one side but the wheel gets hot compared to the other side.

I have been googling and found a minefield of possibilities. I have standard OEM brakes with original brake pipes. The discs and pads seem fine and plenty of life left in them.

Any tips would be very much appreciated as it's going up on axle stands this weekend

If you're comfortable then you can remove the caliper, force the piston out with compressed air and refurb with a refurb kit.

Or you could use this as an excuse to get all calipers refurbed which is really not that expensive (maybe 50-60 quid per caliper).

If the caliper is no longer useable (very unlikely) you can buy a refurbed caliper from brakeparts.co.uk (I used them in the past) for around £70.

It could just be the guide pins (2x 7mm hex bolts that the caliper slides on). Why not simply remove them, clean them up, re-grease and reinstall them and go for a test drive. Would only take ~15 mins..

Philjwb wrote: ↑Tue Feb 12, 2019 5:32 pm It could just be the guide pins (2x 7mm hex bolts that the caliper slides on). Why not simply remove them, clean them up, re-grease and reinstall them and go for a test drive. Would only take ~15 mins..

You should not be greasing the guiding pins, they should be clean and dry. Grease attracts dirt and can be the cause of problems.

thank you so much for all of your advice. What a great bunch on this forum happy motoring guys

Option B, buy big brakes and tell the wife its more safe now?!