Stuck brake caliper M535i

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Alberto89
Posts: 129
Joined: May 04, 2021 5:24 AM
Location: Netherlands

Stuck brake caliper M535i

Post by Alberto89 »

Hi guys,

My M535i stands still a lot, and is hardly ridden. Now I went for a drive yesterday, but notice that my brake on the left rear gets "stuck". If I leave the car for an hour, it comes loose again. Do you think my brake caliper is broken, or are there other parts that are broken? Thanks for contributing ideas.
DFWTX85
Posts: 113
Joined: Sep 27, 2017 10:26 PM
Location: US

Re: Stuck brake caliper M535i

Post by DFWTX85 »

Sounds like one of the rear calipers is in need of a rebuild. One of my cars is suffering from this same issue, where after a short drive (maybe 10 minutes and no heavy use of brakes) the caliper will intermittently stick and eventually release. This makes for a potentially dangerous situation.
Alberto89
Posts: 129
Joined: May 04, 2021 5:24 AM
Location: Netherlands

Re: Stuck brake caliper M535i

Post by Alberto89 »

Exactly! How did you solve it? New on or rebuild old?
DFWTX85
Posts: 113
Joined: Sep 27, 2017 10:26 PM
Location: US

Re: Stuck brake caliper M535i

Post by DFWTX85 »

If you have the tools and ability, it would make sense to order the rebuild kit and do it yourself. I am not aware of new calipers available for purchase. But I'm sure some places offer rebuilt units - I would replace/rebuild both rear brake units at the same time. Otherwise you could experience unexpected or undesirable braking behavior. Also consider replacing the parking brake parts too; springs, shoes, etc.
Alberto89
Posts: 129
Joined: May 04, 2021 5:24 AM
Location: Netherlands

Re: Stuck brake caliper M535i

Post by Alberto89 »

Unfortunately not the tool to do yourself. I am considering new. Thanks for your advice.
dsmith
Posts: 2362
Joined: Jan 20, 2012 12:52 AM
Location: Charleston, SC

Re: Stuck brake caliper M535i

Post by dsmith »

Replace the rubber brake hoses also, unless verified replaced in the last 5-10 yrs. they degrade from the inside and can act as a one way valve that looks like a sticking caliper.
Nothintoseeere
Posts: 57
Joined: Apr 23, 2021 5:27 PM
Location: U.k

Re: Stuck brake caliper M535i

Post by Nothintoseeere »

Pretty easy to do. Dismantle everything. Clean up. Paint the calipers and reassemble with new seals. I remember doing it 10 years ago. I did not have the tools i do now which are mostly for bicycles. Just a limited socket set and spanners.

Unless it the brake hoses
Alberto89
Posts: 129
Joined: May 04, 2021 5:24 AM
Location: Netherlands

Re: Stuck brake caliper M535i

Post by Alberto89 »

dsmith wrote: Jun 04, 2021 7:10 AM Replace the rubber brake hoses also, unless verified replaced in the last 5-10 yrs. they degrade from the inside and can act as a one way valve that looks like a sticking caliper.
Which part is that? Do you have a picture of it?
Alberto89
Posts: 129
Joined: May 04, 2021 5:24 AM
Location: Netherlands

Re: Stuck brake caliper M535i

Post by Alberto89 »

Nothintoseeere wrote: Jun 04, 2021 11:29 AM Pretty easy to do. Dismantle everything. Clean up. Paint the calipers and reassemble with new seals. I remember doing it 10 years ago. I did not have the tools i do now which are mostly for bicycles. Just a limited socket set and spanners.

Unless it the brake hoses

Does the piston have to come out too? I think you can only get that with air? I don't think it's worth it. I have already found them complete for around €70.
Nothintoseeere
Posts: 57
Joined: Apr 23, 2021 5:27 PM
Location: U.k

Re: Stuck brake caliper M535i

Post by Nothintoseeere »

Yes more old calipers. They will benefit from a rebuild also.

Air is easy. Its everywhere and almost everywhere in the compressed form.
dsmith
Posts: 2362
Joined: Jan 20, 2012 12:52 AM
Location: Charleston, SC

Re: Stuck brake caliper M535i

Post by dsmith »

Alberto89 wrote: Jun 04, 2021 11:51 AM
dsmith wrote: Jun 04, 2021 7:10 AM Replace the rubber brake hoses also, unless verified replaced in the last 5-10 yrs. they degrade from the inside and can act as a one way valve that looks like a sticking caliper.
Which part is that? Do you have a picture of it?
If still relevant, like these.

https://www.fcpeuro.com/products/bmw-co ... gIE9PD_BwE
Alberto89
Posts: 129
Joined: May 04, 2021 5:24 AM
Location: Netherlands

Re: Stuck brake caliper M535i

Post by Alberto89 »

dsmith wrote: Jun 24, 2021 5:53 PM
Alberto89 wrote: Jun 04, 2021 11:51 AM
dsmith wrote: Jun 04, 2021 7:10 AM Replace the rubber brake hoses also, unless verified replaced in the last 5-10 yrs. they degrade from the inside and can act as a one way valve that looks like a sticking caliper.
Which part is that? Do you have a picture of it?
If still relevant, like these.

https://www.fcpeuro.com/products/bmw-co ... gIE9PD_BwE
Thanks for thinking along!
vinceg101
Posts: 4802
Joined: Jun 20, 2007 2:40 AM
Location: Los Angeles, CA

Re: Stuck brake caliper M535i

Post by vinceg101 »

A few notes on brake calipers, general and specific:
-If you do decide to go the route of rebuilding, it is actually surprisingly straight-forward and dare say easy but your first one you do will take you the longest (it's just the way it is which is why you buy a few extra kits). The best instructions are on the ATE Boot Rebuild kits. There really are no special tools needed: compressed air (but not a lot), a large C-Clamp works best, a smallish block of wood, a small pick (but used sparingly), the right hex key wrench, nitrile gloves and plenty of towels/rags. The hardest part in all this is the bleeding process at the end; this is where one special tool is invaluable: a power bleeder. It makes short work if you're by yourself. But there are more traditional and conventional procedures well documented. I did a write-up on rebuilding here, but there are others on this site: https://www.mye28.com/viewtopic.php?f=7 ... 5&start=50

-Less frequently used cars and older brake systems are prone to sticking calipers & shoes. The slightest surface rust can cause this on all surfaces including the rotors, especially if you're in a slightly damp environment. Usually initial use will free up the caliper and clean off the rotor, just go slow the first block or two while working the brakes. If that doesn't do it, then stop and get help.

-As you are aware brake fluid is hydroscopic which means it attracts and collects moisture (i.e. water). This is why there is 2 year fluid servicing built into virtually all car maintenance schedules (well there should be). We all tend to overlook this from time to time (me pointing finger at thyself), but it is vitally important.

-Rebuilt calipers are hit and miss on quality. Buying discount is risky since they tend to mass-rebuild these with the cheapest labor assembly line fashion. As such the quality of the rebuild can vary wildly. But I would assume that a place like FCP which has a free part replacement policy would tend to want to get it right the first and only time they do this, so you're likely good with them.

-Brake upgrades: Now would be the time if you wanted to upgrade to E32/E34 Big Brakes especially if you needed new rotors. Everything is bolt-off/bolt-on and you DO NOT need an E32 master cylinder to get the benefits. You will need at least 15" wheels though. And yes, do replace your brake lines/hoses when you do this (you should do this regardless when you replace the calipers since if they're original, the rubber is pretty shot and are likely weeping). It's surprising how much better your whole brake system will be with just new brake lines/hoses.

Good luck.
philipj
Posts: 69
Joined: Mar 10, 2016 7:39 PM
Location: Florida

Re: Stuck brake caliper M535i

Post by philipj »

I have the exact same problem but on the left front, so I got 2 rebuilt calipers plus 2 new hoses... Still have the same problem, but now instead of happening say, after 15 minute of driving it happens after half an hour... I wonder if it is the brake master cylinder, since if I pump the pedal a few times it seems to get loose again enough to drive for a little while longer...
vinceg101
Posts: 4802
Joined: Jun 20, 2007 2:40 AM
Location: Los Angeles, CA

Re: Stuck brake caliper M535i

Post by vinceg101 »

philipj wrote: Dec 23, 2021 7:04 PM I have the exact same problem but on the left front, so I got 2 rebuilt calipers plus 2 new hoses... Still have the same problem, but now instead of happening say, after 15 minute of driving it happens after half an hour... I wonder if it is the brake master cylinder, since if I pump the pedal a few times it seems to get loose again enough to drive for a little while longer...
Likely but it also could be your hydro booster. Check under the carpet and up along the firewall on the driver's side for leaking fluid.
philipj
Posts: 69
Joined: Mar 10, 2016 7:39 PM
Location: Florida

Re: Stuck brake caliper M535i

Post by philipj »

Hello there, there is no fluid leaking at all anywhere, and despite not driving the car much, I keep the fluid clean...
Mike W.
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Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: Stuck brake caliper M535i

Post by Mike W. »

Alberto89 wrote: Jun 03, 2021 5:10 AM Hi guys,

My M535i stands still a lot, and is hardly ridden. Now I went for a drive yesterday, but notice that my brake on the left rear gets "stuck". If I leave the car for an hour, it comes loose again. Do you think my brake caliper is broken, or are there other parts that are broken? Thanks for contributing ideas.
I had a problem for a time where if I sat with the brakes on, not hard, but say sitting talking on the phone for a while, my left front would lock up. I found if I pressed hard on the brake pedal it would release the stuck caliper. Not exactly a fix, but easier, if it works for you, than leaving it sit for a hour. I'd already rebuilt the calipers a couple of years previous, easy job on single piston ones, but didn't do it again.
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