Mk5 Volkswagen R32 Brake Caliper Rebuild

I recently bought a set of front Mk5 R32 and rear Mk6 R calipers so rebuild and refinish for the AWDTAXI. The original ones are starting to look pretty tired and they have 151,000 miles on them. I bought a second set so that the car wouldn’t have any down time during the process. I stripped them all down and sent them to powder coat (which that is another story) and figured I would document the reassembly for others that may want to do the same thing. The main things I want to highlight here are the rear caliper seal kits, of which there are none listed as actually fitting the R32/R, and the process for install new front piston boots, which is a pain without the proper tool.

One thing to mention, I installed the TyrolSport front caliper slide bushings and I don’t detail that process because it has been done many times already. I have them on my existing calipers and love them so it was a no brainer that I would use them again.

If you have any questions, please comment below or shoot me an email. Please share with anyone that might be on the fence about doing this job because I am sure it will help a little.

Front R32/R Calipers

The front calipers are pretty simple to take apart and it is safe to assume that if you took them off the car, then you are capable of taking them apart. I didn’t document the dismantling but its straight forward and the one thing that you can find online is removing the piston using air (please be careful doing that).


1K0-698-471-A - This is the OEM piston boot and seal for one side, so you will need two. You can be my guest to try aftermarket boots and seals but I had zero luck getting any of them to fit properly. I mostly had problems with the boots and not the seals. I know the OEM ones are expensive, but they fit right.

T55 torx driver

T30 torx driver

7mm allen driver

11mm wrench

T10145 - This is the OEM brake tool used for compressing the front piston and it is also used for installing the front boots. Believe me when I say that I went through several boots trying to get them on without the proper tool and tore them. Just go to your local dealer and ask if they have it and if they can just have someone press it on for you. Or you can buy the tool…it isn’t cheap though.

T10146/2 - The OEM brake tool has six different cups for different purposes. This one is specifically used on the front boot.

Brake slide lube - I am a big fan of Permatex and it is available HERE from Amazon.

Piston compressor tool - I have an old Matco tool but there are so many others out there on Amazon, like THIS one


You are going to start by putting the two pieces together. There isn’t much room for error here and put the bolts into the holes. The longer two go in the inner two holes and the shorter two go in the outer. Go ahead and tighten them down. Also make sure the brake line is installed with the 11mm wrench.

Next is attaching the dampers with the T30 bolt. Make sure the washer is on there first.


Once the inner piston seal is in, it is time to address the piston boot. This is different from most piston boots that sit into a groove. This kind is pressed over a lip.


Using OEM VW tool T10145 and T10146/2, spray a lot of silicone lube on the inside of the boot and insert it into the cup.


The tool is hand threaded to push the boot over the lip. Make sure it is sitting as level as possible before applying pressure.


Once the boot is on, you carefully insert the piston into the boot. Make sure nothing is twisted or pinch and once it is in, you can press in the piston. You may need to use a piston compressing tool but I was able to press it in by hand (if there is enough lube it should be tight but still move).


Now that the piston is all done, let’s move to the carrier. The slide pins are put on with a 7mm allen driver and lubed up. I put a very small amount of high temp anti-seize on the threads of the pins before installing.


That’s it! The hardest thing to do is the boot so as long as you get that handled, the rest is cake.


Rear R32/R Calipers

The rear calipers are more in depth than the front and for the Mk5/6 R32/R calipers, not nearly as much information available as other models. I did not document the tear down but I hope you are smart enough to realize you can just reverse my installation photos.


Centric Parts 143.33032 - this rebuild kit is available HERE on Amazon and includes the piston boot (41mm piston), piston seal (41mm piston), donut seal for inside the piston, snap ring for inside the piston, donut seal for the parking brake actuator shaft, and the crown seal for the parking brake shaft and lever. This kit is for one side so you will need two.

Lube - I used some leftover Lucas assembly lube and silicone spray lube that I had in my box. Feel free to use what you have.

T30 torx driver

13mm socket and ratchet or 13mm wrench

11mm wrench

Master cylinder snap ring pliers - I got mine HERE from Amazon. I am sure I will need them in the future for other projects.

Small straight head screw driver

Brake slide lube - I am a big fan of Permatex and it is available HERE from Amazon.

Piston compressor tool - I have an old Matco tool but there are so many others out there on Amazon, like THIS one


First, you will need the crown shaped seal that fits into the rear of the caliper where the parking brake lever sits. Put a little lube around the seal to allow it to press in.


The actuator for the parking brake goes in next. There is a hole in it that matches up with the nub inside the chamber. After replacing the donut seal, put a little lube around the grooved section of the shaft and insert it into the caliper.

Putting the snap ring back in can only be described as a royal pain in the ass. Using master cylinder snap ring pliers helps a lot but you will also need a small and long straight head screwdriver to push the ring down while compressing the ring AND making sure the actuator stays seated. It sucks and takes some time. I am sure part of the difficulty comes from the brand new donut seal.


I know it is a terrible photo and even looking at it now, I see that it does not show the snap ring fully seated. I did get it seated after this photo was taken but for ease, I tried to put the ring back in the same spot from when I took it out. I don’t know if it matters but I used the punched numbers on the actuator as a reference point.


When putting the parking brake lever and line brackets on, make sure you have the correct ones for the correct side. Start with the larger one and don’t tighten the T30 all the way. You will need a little movement for putting the lever on the grooves.

Make sure the lever is on the grooves so that when no tension is applied it is resting against the stopper. Tighten the 13mm nut by hand to press the lever all the way down. I put one dot of Loctite on the threads.


The spring can be kind of tricky if you don’t go in the correct order. You want to put the non hooked end in the lever first and then put the hooked end into the groove. It will naturally click into the small part of the L. Make sure the T30 is now tightened since all is in place.


The brake line is put in with an 11mm wrench and make sure the other end lines up with the bracket, centered in the hole.


Time for the piston. I used silicone spray lube on the piston and boot and what I did was slid the boot all the way to the open end of the piston and put the boot into the caliper grooves. It will take a little work to get it seated right but this is better than everything I read about it seating itself once the piston is fully compressed.


Once the boot is in, use your typical caliper compressor tool to push in and twist the piston all the way in.


Use your brake lube of choice to lube the slides to go back into the carrier. I prefer Permatex’s purple ceramic lube since it has a super high temperature rating. One thing to note, if you have two different style slide pins (a tapered and a non tapered) the more solid one, or non tapered, will go in the bottom position. My original R32 pins are identical but the Mk6 R calipers I got have different ones.


There you have it! I hope this helped in some way and saved you from having some of the same headaches that I had throughout the process.


BMW ///M 235i

Chip brought his 235i back for it's first wash after being coated a month ago. It is important that after coating, the vehicle does not get washed for 7-14 days in order to allow the coating to fully cure and harden. I usually have my clients come back at the 3 week mark for their first wash which is included in the price of the coating. Also, this is the time when the included Opti-Coat wash kit gets picked up! Be sure to watch the video of the 235i before and after Opti-Coat Pro…it’s not magic, it’s science!