How To Rebuild A Brake Caliper (New piston, seals etc)

How to rebuild a brake Caliper and rebuilding the brake calipers with a refurbishment kit that includes new piston, seals, boots and bleeder screw.
Patreon: / georgeausters
The following links are affiliate links that the channel recieves commission for
Tools I Use!
Small Dewalt Impact Wrench: amzn.to/2T4igdi
Big Dewalt Impact Wrench: amzn.to/39NOrEu
Dewalt 5ah Battery: amzn.to/39tRRhL
Dewalt Battery Charger: amzn.to/3dkwlxb
Sealey Impact Socket Set: amzn.to/3a8zcpQ
Torx Socket Set: amzn.to/32EbnDV
Female Torx Socket Set: amzn.to/2PzAZMQ
Torque Wrench: amzn.to/2VF0YpI
Oil Drain Pan: amzn.to/3dm00pJ
ISTA D / BMW Coding Kit: ebay.us/qBKS6s
➢ Subscribe For Regular Videos ➢ goo.gl/x0Juyl
➢ Instagram: / georgeausters
➢ Facebook: / georgeausterspage
➢ Email: [e-mail]
➢Amazon Prime Free 30 Day Trial: amzn.to/2v6kVe5
➢Best Place For Car Parts: bit.ly/2swCcMz

[@jonowen6612]

Great video George! When I watch British car repair vids I’m amazed by the rust, but then I remember you’re an island nation surrounded by salt water.

[@GeorgeAusters]

Hahaha very true!

[@williamwinn948]

you can also pump the brakes to pop it out that's what I did. great video

[@bilbobagins1653]

Your videos are the best for guys like me (amateurs), every details well explained. Thank you Bro!

[@mr.t2585]

Nice video George. Just a little tip.. when installing outer dust boot it is easier to put boot on lip when the piston is out of calliper. Slide boot to the lower edge of piston and then slide the piston trough boot.

[@GeorgeAusters]

Interesting👍🏻

[@OttoKaarelAltroff]

i do not recommend this method of putting the boot on the caliper first. I just managed to tear the boot from the inside when trying to slide the piston in later..even though i was super careful. Thumbs up for the method shown in the video!

[@conradbegin9505]

​@ OttoKaarelAltroff

[@bigmuvver]

Great video, very clear on the procedure. I resealed all of my callipers last year and this year I am starting on the fronts with new callipers, painted and new discs and pads so will be watching out for your video on the discs and pads changes to get some more great tips. Keep up the great work George.

[@GeorgeAusters]

Cheers Stephen, should have that video up soon enough!

[@lefterisstasi8705]

it is VERY easy to tear or puncture the seal. once you get piston in with seal, use an airline to pressurise the boot. This will make it expand enough to seat itself on the caliper. This is the only way which worked for me. Also remember to make good the points where the pad edges contact the caliper. Rust stops the pads moving in when they wear which side-loads the piston to the point where it seizes.

[@hiiamyu]

I have been waiting for this video for a while. Again, very detailed video. I love it! Thank you!

[@GeorgeAusters]

Thanks for being patient, again much appreciated🙏🏼

[@Bamsi96]

Good job George! I have Discovered you bevause of timming chain for my n47. You have no ideea how much it helped me that series. Greetings from Sweden.

[@GeorgeAusters]

Hi Alin, glad to help. Thanks!

[@ziauddin7948]

excellent installation of new front break piston & inner & outer rubber seals #

[@kardan1984]

Brakes 😬. You have done great job mate! Keep it going 👍

[@GeorgeAusters]

Cheers mate, it’s time to get this thing on the road!

[@joemama-jsg]

Literally saved my life thank you!

[@GeorgeAusters]

Glad to help!

[@dogbite5509]

Another fantastic video - great, clear explanation of work needed and work carried out. I use silicon grease on the slider pins of my brake calipers. I would be confident to strip down the calipers on my brakes after watching your video. Thank you.

[@GeorgeAusters]

Thanks man, appreciate that. Yes silicon grease works just the same!

[@starsaan8304]

Hey, nice video thank you for helping me and my e87 250.000km ! I’m from Belgium but nobody does that as well as you in French 😂

[@GeorgeAusters]

No problem 👍

[@MrVARhythm]

My gf and I love watching you lubricate pistons.

[@rogermay808]

Great to see someone repairing. Any Muppet can bolt a new part on. I prefer to repair not replace.

[@GeorgeAusters]

I’m the exact same, no point throwing parts away if they’re easily saved!

[@BigUriel]

Thing is a rebuild kit costs 25 quid and a new caliper cost 50. You have a lot more work to save 25 quid...assuming the rebuild works, because you might have rust on the caliper body around the piston, you could also easily damage the seal and they don't sell it separately so you'd have to buy another kit...is it work the risk and hassle to maybe save 25 quid if all goes well, when you know for sure a new caliper will work straight away and you can change it in half hour and be done with it?

[@trollmato]

@@BigUrielrebuild kit costs 12-15 quid buddy

[@lisaholt3218]

Best to put boot on inner end of the piston and seat seal while it's on the piston before pushing it in .then push piston trew New boot only takes seconds and no screwdriver stuffin needed

[@carlsherwin5557]

I'm doing mine now on the front, can't get the outer boot on caliper it seems real tight

[@GeorgeAusters]

Yeah it is tight, need to keep pushing with a screwdriver

[@DameAndThatGame]

Maybe a small tip out of 100s 😂, maybe a skinny screwdriver pushed down the bleeder screw hole to push the piston. Also cheers. Looks really easy, gonna do mine soon now, cheers

[@hollybrandoncainmoore9751]

You said little grease on the slider pins after you dunked them in the bucket of red grease lol thank you that was funny great video good job

[@rohky5452]

Way to figure out piston size without taking it out? some sites says 42mm some 44mm

[@jacobgame999]

Ate recommend not to put grease on caliper guide pins. The reason behind it is simple, the friction between guide pins and rubber cover helps maintaining proper gap between pad and brake rotor by backing off the caliper

[@Dnasty1]

Great video. I dunno how you got that last lip in that’s currently where I am stuck. However I didn’t use any grease and I think the kit is not an exact fit. Getting the caliper cylinder in was a bit difficult also but getting it out was a breeze. I sprayed compressed air in the brake line hole and it popped right out 😂 used wood blocks to catch it of course. I was also wondering if I soak this in degreaser can it damage any of the internal components?

[@tonikesti7756]

I have the same caliber and the same metal ring came off when I took away the old piston boot. I just can't understand how to pop the new boot in, because there's no groove where to pop it in 🤔. It just comes right off if push it all the way in, because there's nothing retaining it.

[@neillers100]

Great detailed video as always. Cheers 👍👍

[@GeorgeAusters]

Thanks Neil!

[@jonsutyautomotiverepair1993]

Good video mate, i don’t do value or rebuilds due to the extra time needed, but if they’re cheap enough you’ve given me something else to think of!. Good luck In your KZbin venture

[@GeorgeAusters]

Cheers mate👍🏻

[@jessevalouch4155]

It's very important to point out that you should NEVER use any type of grease on rubber seals except for silicone based grease.any Petroleum based grease WILL cause the rubber seals to swell and cause the caliper to stick/seize.

[@MS-we4wi]

The grease that comes with the caliper rebuild kit is silicone based, right?

[@dili00007]

I was also questioning what would happen when the grease mixes with the brake fluid in the caliper. Once I start the install process I change my rubber gloves and use brake fluid to lubricate all the parts back in. I want the brake fluid as pure as possible.

[@chadriddle3517]

Great video George! Love the step by step process

[@GeorgeAusters]

Cheers Chad!

[@nameismetatoo4591]

Did mine today but after bleeding and going for a test drive I found the brakes to be pretty spongey and unresponsive. They can just barely provide enough force to engage ABS when I really floor the brake pedal, but they used to lock up much sooner. I'm wondering if I should have filled the cylinders with brake fluid before reattaching the brake line, as I'm not sure if the bleeding process is able to get all the air out of the cylinder. It's also possible that the old pistons were just not retracting very far, thus reducing the travel needed to do hard braking (in other words, what I feel as "spongey" is actually how they should feel and I am just used to sticky brakes).

[@Automan9]

The ABS system needs its own bleed I reckon

[@craigcroly6131]

I have same issue new to doing me mechanicals on my car?

[@chantellemalherbe643]

Hi george thanks for your video, I am trying to fit out piston boot and it will not fit no matter how hard I try, what else could I try?

[@GeorgeAusters]

It will fit but it’s tight, I generally use a flat bladed screw driver to push on the outer steel ring but be careful not to split the boot👍🏻

[@iandaw2363]

Great vid George

[@GeorgeAusters]

Cheers Ian!

[@STBRetired1]

Oh for crying out loud, you're a life-saver (if I haven't botched up the job too much already). I was under the impression that no grease was compatible with brake fluid so I only used brake fluid to lubricate the O-ring and piston surface. Now the piston is in crooked. I'll bet if I used some of that red rubber grease, I wouldn't have had such a problem sliding the piston past the O-ring. Be careful when you Google "red rubber grease" because a lot of the results will be that Lucas Red "N Tacky grease which is something different. I see off to the side that Castrol sells a "Red Rubber Grease". I've seen it in a Castrol container and in a white container on Amazon. Now I've got to get me some and hope I can remove the jammed piston from the caliper without destroying the new rubber dust cover. Actually, why not destroy it. They're cheap. Thanks for posting your video otherwise I would never have known about that red rubber grease.

[@GeorgeAusters]

Glad to help... Yes most piston kits actually come with grease to use

[@STBRetired1]

@@GeorgeAusters Apparently O'Reilly's auto supply store doesn't supply the grease with their O-ring and rubber dust shield. That's why I never knew about it. But, I got the jammed piston out. 90 psi of air pressure does wonders. Of course I had a piece of wood for it to bang against instead of the steel caliper. Now I'm just waiting for my red rubber grease to come across the ocean. Is that a mainly United Kingdom product? It's made by Castro which we have here but no one seems to carry the red rubber grease.

[@GeorgeAusters]

Not sure but it’s been around for a while

[@chris-dt8qf]

Hi George, Where did you find the rubber plug you have on the end of the brake hose? I have been looking for something like that a while. This will remove the need to have something clamping down on the hose.

[@GeorgeAusters]

It was just from a new fuel filter

[@WilliamVG]

Where do you find the rebuild kits? Ebay best bet?

[@mikeball1615]

Hi George. Great video, just curious where you got the parts from? Ie the piston itself, did it come as a complete kit. The biggish places I've tried don't sell them and BMW only sell the piston as part of the main caliper so it becomes really expensive!

[@GeorgeAusters]

Pretty sure this is the kit I used: ebay.us/raqGHf

[@fernandoruifaria5417]

I had to do the same in my 120d.

[@officialwillieg2001]

great video mate

[@GeorgeAusters]

Cheers mate

[@neilpike4358]

George, another excellent and very informative video, Are you a mechanic by trade? Just found your channel recently and I’m well impressed with your knowledge and tips.

[@GeorgeAusters]

Thanks Neil! No I’m not a mechanic, everything is pretty much self taught👍🏻

[@neilpike4358]

Well done mate keep up the good work!

[@martinbeach6001]

Really great video you make it look so easy 10out10 nice one George peace

[@GeorgeAusters]

Cheers Martin!

[@786free1]

Thanks, that was very helpful. Do u have to bleed the brakes after reinstalling the caliper?

[@GeorgeAusters]

Yes

[@786free1]

@@GeorgeAusters ok. thanks

[@simon_sjw9973]

Cool video George man

[@GeorgeAusters]

Cheers Simon👌🏼

[@HabaneroTi]

I know that quality calipers are built like tanks but when I rebuild them I prefer to remove all the cruddy rust, clean them up and treat and paint them with something heavy duty like POR-15 or KBS. They not only look a lot nicer this way but they're going to last longer, stay cleaner and be easier to work on.

[@GeorgeAusters]

I did paint them later

[@przemokbh8079]

Hey. Where I can get this cap for dripping brake fluid? Super video

[@GeorgeAusters]

It’s custom made

[@przemokbh8079]

@@GeorgeAusters ok thanks.

[@ia3423]

Great video, just one question, how do you get the trapped air out from the callipers?

[@GeorgeAusters]

Brake fluid flush👍🏻

[@Gamer4Retribution]

for some reason i cannot even get that inner seal back in it just wants to keep popping out on the opposite side i have in. IDK What to do??

[@Gamer4Retribution]

we got it we biougt a brand new kit and everything

[@driveline1294]

Great job

[@DocMackGarage]

Nice video. Do the rear rotors need doing ?

[@GeorgeAusters]

Not sure but I will be doing them👍🏻

[@americantruckeringermany8394]

good job, my rear pad is grinding metal on metal because it wont retract

[@americantruckeringermany8394]

Yes I tried removing the piston.. it won't come out neither haha. Had to order a whole new caliper. Jesus 23 year old is annoying

[@SKETE_B]

Did u have to bleed the brakes after installation.?

[@GeorgeAusters]

Of course

[@SKETE_B]

Sound man I'll be tackling same job at the weekend hence why I asked

[@mshahid2898]

Great Job 👏🏼 - I would have greased the inside of the piston housing too. To get a bit more grease in. Keep up the cool vids ✊🏼

[@GeorgeAusters]

Thanks man, yeah doesn’t hurt to!

[@terrybowman604]

Grease will hold dirt and sand. Use as little as possible. I do use a little on the slides, because they are covered with a boot.

[@KhanNakash]

Great job!👊👍

[@GeorgeAusters]

Thanks Nakash!

[@welitonsilva1824]

Vídeo muito bem explicado parabéns 👏

[@dcfgarage]

Very nice video, Thanks!

[@GeorgeAusters]

Thank you too!

[@Ally.MacMillan]

Thanks for sharing George, they get in bad nick at times eh

[@evaldassarocka4539]

next time try to blow some air with compressor. It will push piston out of calliper in seconds. Just be careful with your fingers cuz it pops out quickly and piston bumps into calliper wall. Ask me how I know

[@highzoo3305]

Do bmw sell those pistons oem? Or you buy them aftermarket? Cheers

[@Ally.MacMillan]

BMW don't make their own calipers and pistons etc. to my knowledge, they will typically get them from Brembo, TRW, Bosch etc. You can find spares on the likes of Autodoc, decent prices, OE quality.

[@miissyb5890]

Great vid as always 👌🏻 Did u have to bleed the brakes when you re installed the calipers?

[@GeorgeAusters]

Thanks 🙏🏼 Yes I did do a brake fluid flush.

[@socommaster]

How many miles?

[@vp5]

Nice video yet again George. Where do you get the orange gloves from? Are they expensive for a box of 100

[@GeorgeAusters]

Thanks man! Here's the link: ebay.us/n0Gkb5

[@johnmc7ify]

Great video George, you are getting there 👍

[@vp5]

Since covid started, rubber gloves.are now 20 per box. Were 6 - 12 pounds per box

[@Ralphfridge1]

I use an airline to pop the piston out

[@garycook1517]

great job

[@GeorgeAusters]

Cheers Gary!

[@andyhunt457]

Bmw want them dry to extend the life of the caliper...🤣🤣🤣

[@ecotts]

No bleed process?

[@GeorgeAusters]

I have some more bits to do yet before I bleed them don’t worry👍🏻

[@justinf1343]

Compressed air will pop a stuck piston out.

[@leenevin8451]

does it drive a lot better?

[@GeorgeAusters]

Haven’t taken it for a proper drive yet but will be next week👍🏻

[@LordDuren]

Where can i get these caps that stop brake fluid from leaking?

[@GeorgeAusters]

You can’t, they’re custom made by my dad

[@katfish6663]

Why the hell didn't you use air on the bleeder hole and blow out the Piston 😢

[@GeorgeAusters]

I didn’t have an air compressor then

[@UsualYaddaYadda]

... and this is the trickiest bit... ...so here's one I did earlier... Me: Dammit!

[@arnietwo11]

Good but cant believe you didnt clean the calipers up more and paint them ??

[@GeorgeAusters]

Like I said, you can keep going and going but it’s not worth it at this stage. I need to get this running 100% first then I can focus more on the cosmetic side of things👌🏼

[@mechanich1249]

Professional! Dont quit our job mate loool

[@ziauddin7948]

excellent 👍🇵🇰

[@Icepressa]

stick a shim and pump the brake next time works like a charm

[@Icepressa]

@@Ally.MacMillan wtf you talking about, as soon as you pump the brakes the piston will fly out, try it and let me no what happened, im a mechanic and if you dont put old pads or somethigg when pushing the piston out it will fly out with fluid, thats why i said shim it so you can get it moving

[@Icepressa]

@@Ally.MacMillan are you fucking stupid or something kid, go outside go take your caliper off and pump the brakes see how fast your fucking caliper piston comes flying out, the reason you shim it is so it doesn’t come flying out with the fluid everywhere you, you get it moving so you don’t need to struggle pulling it out,🤡 GTFOH your not a mechanic nor do you no anything about rebuilding calipers, stick to your car detailing bud

[@Icepressa]

@@Ally.MacMillan are you fucking dumb buddy? it certainly does when the caliper is seized you clown and you pump it a few times, nobody said it comes out with 1 pump kids like you is the reason i know ill still be making money in the future, dont try to tell me something that just happend to the young apprentice this week........your probably 1 your self 👍

[@DanielleAusters]

🙌🏼

[@GeorgeAusters]

👌🏼

[@ericcaumari3957]

Only use brake fluid when you rebuilt the caliper, nothing else, you have already contaminated your oil with grease.

[@gageackley-dechant3146]

The intent was fine, the advice is bad. Don't grease the pistons or piston bores. You will contaminate the brake system and fluid by doing so. If lubrication is needed, use the correct brake fluid for your car, fresh of course. And do not use grease on slide pins or anything rubber. Silicone paste should be the only lubricant that touches rubber, and same with slide pins. Silicone or ceramic only. I've seen this mistake made too many times. You will be buying new calipers and brackets if you do the same.

[@GeorgeAusters]

Lol done this many many times and never had an issue!

[@789costela]

My car has not even got over 3k miles & i have alredy changed brake disck brake pads & both front caliper & handbrake wires 🤨 & o it is not a bmw...

[@GeorgeAusters]

3k miles from new?

[@789costela]

@@GeorgeAusters yes I bought it new

[@leenevin8451]

is it a race car?

[@789costela]

@@leenevin8451 no 😂 not EVEN close ! 🤣, tho it wighete under a ton (bad englis!)

[@txmball1993]

instructions unclear: i popped the caps but got arrested....

[@GeorgeAusters]

😂

[@DrElectron1]

You didn't bleed the refurbed calipers before declaring the job was done. I can just see an inexperienced DIYer following your video and then taking the car for a spin with no brakes.

[@GeorgeAusters]

I’ve made numerous videos showing how to do a brake fluid flush.. I’d say it’s pretty much common sense to bleed your brake fluid after opening the system

[@chrispalubeskie3256]

the pads and rotors were done on that car, putting them back on was retarded, also outer seal should be set in then piston placed through it, this video shows what not to do

[@GeorgeAusters]

I replaced the discs and pads in a separate video👍🏻

[@bimatube1274]

I don’t understand how can you take the caliper off and not even clean it good! Lazy? Is like you buy new clothes and don’t have a shower. I hope that’s not for a client, that’s one of the reasons to DIY and never trust mechanics.

[@GeorgeAusters]

I did clean it? It’s just surface rust

[@bimatube1274]

@@GeorgeAusters No is dirty with a new piston. It just take 30 min to sand it.

[@keytesofessex]

What a waste of life , waiting for the ads to finish

[@harrisonlloyd9668]

Why didn't you blow the piston out with compressed air? Out of curiosity... That's how I always do it