# How to replace your rear calipers, pads and discs



## TheVarix (Apr 3, 2013)

As I could not find a good, clear tutorial on changing Audi calipers, etc...I decided to take a lot of pictures while doing this job to see if it can help others trying to do the same or similar thing. 
Many thanks to all forum members that helped me in my other threads asking about bleeding sequence, etc... Your info was, as usual, invaluable. 
Before I start, I am not a mechanic and this was my 1st time doing calipers so please let me know if you spot things I've done wrong, that I could have done differently (better, easier, etc...) or that I've missed so we can add it.

This is a work in progress as I am writing off the top of my head. I'll include torque specs, hex bit sizes, etc... later on.

Things I bought beforehand:

-- Obviously discs and pads! 
I bought Pagid Discs and Pads (Note that the discs are coated with an anti rust paint both in the friction and non friction areas. Not to worry as after a few moments driving you'll get to the bare metal on the discs and it won't interfere with the pads' performance.








--Rear calipers (Initially one but after being unable to compress the piston on the other caliper I had to buy another one...
They are Audi branded, exactly the same as the ones I had fitted but in the box it says Pagid (I am not sure, they might just re-manufacture them using their own products for the pistons, seals, etc...) 
I also bought 2 litres of brake fluid ESP DOT 4 for cars with ESP (apparently it has lower viscosity) and a bleeding kit










The bleeding kit is quite cool as it has a one way valve that prevents air from going back up the tube into the caliper (that way you can do it by yourself without helper!)










Then I painted the calipers red using Halfords red caliper paint










Step by step

1) Remove rear wheels and put car on jack stands.

2)There's a Phillips retaining bolt holding the disc in place (it needs to be removed but most likely it will be very rusted and you'll only damage the thread if you try to undo it)
Get an impact driver, place as perpendicular to the disc as you can and hit it with a hammer (it was so easy with this tool!)










3)Undo the hand brake cable from the caliper mechanism. First remove the retaining spring (you can see it in the picture, hanging) Then you'll need to pull the lever (number 2) down and with a screw driver move the ball end of the cable (number 3) until you can detach it. 
You can do it either with a ratchet by turning the bolt in the mechanism (number 1) or using pliers. You will see that the lever will rotate down giving you room to detach the ball end of the hand brake cable.










Once you have detached the cable you can then proceed to remove with a flat head screwdriver the clip that holds the cable in place and then pass the whole thing (cable and rubber boot) through the hole)










4)Loosen the bolt that goes at the top of the caliper (where the brake line goes) to have it ready for the removal of the caliper.

Then undo the 2 bolts for the caliper slider pins (you'll need: 11mm bit for the ratchet and a 15 spanner)










5) You can then remove the caliper (be careful and don't let it hang as it can damage the brake lines, I put whatever I had at hand underneath (a tin of paint, etc...)

-- Note how rusty everything was!!










6)Remove the 2 hex bolts that hold the caliper carrier in place and remove it so you can remove the disc.










7) Remove the disc and fit the new one. Note: I replaced the disc retaining bolt for these others I bought online made of stainless steel and with a hex head (I also put some copper grease on the thread)










8 ) Clean and regrease the caliper slider pins using silicone grease










9) Refit the caliper carrier, peel off the cover for the adhesive in the pads and slide them in place.

10) Go to the brake fluid reservoir and remove the cap.

Then finish undoing the bolt on top of the square box where the brake line goes and you'll be able to completely remove the caliper. Have the new one at hand and quickly refit the brake line, trying to lose as little fluid as you can (minimising the amount of air that gets in) 
Note: the new calipers come with 2 copper washers that should be replaced (one goes at the top of the bolt and the other goes at the bottom of the square bit the bolt attaches itself to.










Note: it was a step that I had to do quickly so could not take any photos!  
While doing this, keep an eye on the brake fluid reservoir and try not to let it get empty!! (I almost got it empty when replacing the second one as I lost a bit too much fluid)

11) Bleed the wheels at the calipers. Undo about half a turn the bleed nipple and fit in place the bleeding kit (make sure it's tight!) 
Go to the car and press the brake pedal a few times (you'll see some air coming out). Keep doing this until the fluid comes clear with no bubbles (keep an eye on the reservoir and top up when needed)

The sequence I followed was: Near side rear / Offside rear / Near side front / Offside front
(Hoggy and the Bentley manual suggested a completely different sequence, starting from the front)

Press a few times the pedal (don't go all the way down) and keep an eye on the tube and reservoir until the fluid comes without bubbles (you'll have to get in and out of the car all the time!)

Note: there was one bleed nipple that was all rusted and wouldn't turn. I used this product "Shock and Unlock" from Halfords. I sprayed a lot of it for a few seconds and then I tapped the nipple with a hammer. It worked great!!










12) Refit the handbrake mechanism (using the same procedure as before) Remove the return spring first. Then rotate lever using centre bolt to make room for the ball end of the cable. (See last set of pictures at the end)
Make sure that once you refit the cable, the gap between the "stop"lever and the lever itself is less than 1mm. We attach the cable only at the end as if you try to move the lever mechanism without fluid/pressure in the caliper you would need to reset the mechanism!)

12) Test the car. Turn the ignition on and start the engine. See how the brake pedal goes. Mine was quite spongy and soft, with quite a lot of travel. If this is the case, you'll have to bleed the master cylinder!

Underneath the reservoir there are 2 bleed nipples.










They are the ones you need to do but as you can see they're a bit tricky to get to. I used a combination of ratchet extensions and universal joints with a 7mm socket to losen it up (about 1/2 a turn)










Bleed in any order the same way as the calipers, until fluid comes clear. (I did the closest/easiest first though)

Bleeding the master cylinder did the trick and the car's pedal feel was now as it should. I took the car to my local Audi Indy for peace of mind and he said that it was normal after new fluid, pads, etc.. for the brake to feel a bit softer than before

Here are 3 pics: one of the fitting of the hand brake cable and 2 of the finished product:










Hope it helps someone but please remember, you're working with the brake system so be careful and do this at your own risk!


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## Skeee (Jun 9, 2009)

viewtopic.php?f=56&t=172191&p=4094769#p4094769
Linked it to the KB Index.

Excellent write up and pics.

Silicone grease on the guide pins should be ok but mightn't last long as not ideal for high temps.
I'd recommend, after you've cleaned them (_in the end of a drill with Brasso!_) a light smear of
"High Temp Lithium Soap Paste" Moly G-3407 or TRW PFG110 
https://www.merlinmotorsport.co.uk/p/tr ... gmc-grease


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## outdoor stevie (Nov 24, 2013)

Absolutely smashing, clear, easy to follow with good pics well done lad.

Stevie


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## Pugwash69 (Jun 12, 2012)

Great photos and nicely written. All I worked from was a youtube video where the bloke kept standing in the way of the camera. 8)


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## warrenstuart (Mar 3, 2010)

Excellent write up, well done [smiley=thumbsup.gif]

Bookmarked for future reference.

Warren.


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## TheVarix (Apr 3, 2013)

Skeee said:


> Silicone grease on the guide pins should be ok but mightn't last long as not ideal for high temps.
> I'd recommend, after you've cleaned them (_in the end of a drill with Brasso!_) a light smear of
> "High Temp Lithium Soap Paste" Moly G-3407 or TRW PFG110
> https://www.merlinmotorsport.co.uk/p/tr ... gmc-grease


Thanks for the tip and link! I used silicone grease in order not to damage the rubber boots as normal grease apparently would (I have been told)


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## droopsnoot (Sep 5, 2002)

On the subject of fluid loss when changing calipers, you can buy brake line clamps that you would use to clamp the flexi hose near the caliper, which greatly reduces the amount of fluid that drops out. You could use a G-cramp and a couple of bits of something soft to protect the hose, but you could easily over-tighten something like that, where the clamps are not expensive and intended for the job. Also you'd clamp around the centre of the hose, so that you're not damaging the end connections.

You still have to bleed the brakes, of course, but you haven't got to be quite so speedy about swapping calipers. Interesting note about bleeding the master cylinder - mine has had a soft pedal for a long time, I wonder if that's why.

Great write-up though TheVarix, and good pics - mine haven't been done for a while, so it's only a matter of time, and threads like this make it all so much easier.


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## poor1 (Dec 28, 2011)

I too use clamps on the hoses before detaching the calipers to prevent air entering the system. It's a widely used practice. However as it was pointed out in another post on the subject the hoses on the TT are not rubber and sometimes do not fully regain their full shape afterwards. If using clamps use the correct tool and not under any cicunstances things like mole wrenches which will damage them.

The only other thing I would recommend is to use a proper pressure bleeder, such as the Motive or Draper ones. It makes brake bleeding a very simple operation.

Good comprehensive description.


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## Stevey83 (Oct 16, 2011)

Gunson easibleed reccomended for these jobs!


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## Cornwall (Apr 8, 2013)

Great bright up and excellent photo's well done for taking the time to do this.

It will no doubt help many others, good job


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## TheVarix (Apr 3, 2013)

Thanks everyone for your replies. Regarding the clamping of the brake lines, I know it's a common procedure but in this car apparently it can only be done safely at the front and not at the back. In a previous thread of mine, I asked about bleeding and another forum member suggested that clamping wasn't a good idea as the inside of the lines at the rear is made of kevlar or some sort of material like that that won't recover its shape once bent.
We need to get more info regarding this. I am going to have a look at the Bentley manual today and see if it mentions anything about it. Will update the thread with whatever I manage to find out.


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## poor1 (Dec 28, 2011)

The Varix
Clamping. Yes that is the post I was referring to. Whatever the material is it does not fully regain it's shape like conventional lines do despite the considerable pressure inside the brake line. However it is very slight and there is no long term problem as far as I know.


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## Hoggy (May 8, 2002)

Hi, Never known the OEM rear brake hoses to be any different from the front. Never had a prob clamping hoses in the past, although usually always new hoses.
Hoggy.


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## David C (Apr 15, 2013)

TheVarix said:


> --Rear calipers (Initially one but after being unable to compress the piston on the other caliper I had to buy another one...


The rear pistons don't just push in, they need to be pushed & turned at the same time.
Easy with the proper rewind tool.


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## dopeyonspeed (May 17, 2012)

I did find you have to watch out you dont cross thread the bolt on the box of brake line as very closely threaded. Finger tight first


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## dopeyonspeed (May 17, 2012)

David C said:


> TheVarix said:
> 
> 
> > --Rear calipers (Initially one but after being unable to compress the piston on the other caliper I had to buy another one...
> ...


Clockwise I believe


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## TheVarix (Apr 3, 2013)

David C said:


> TheVarix said:
> 
> 
> > --Rear calipers (Initially one but after being unable to compress the piston on the other caliper I had to buy another one...
> ...


I know. I have a caliper rewind tool and have used it before. 
In fact I had taken these pictures with the 1st caliper I bought to demonstrate and include in the "how-to" 
You just select the correct side of the disc, fit in the piston slots, adjust the base so it's tight and rotate clockwise.



















No matter how hard I tried, it wouldn't retract past a certain point (with the tool)
After removing the caliper, I inspected the piston by lifting the boot up and saw signs of damage caused by rust, dust and debris so it definitely was seized.


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## TheVarix (Apr 3, 2013)

dopeyonspeed said:


> I did find you have to watch out you dont cross thread the bolt on the box of brake line as very closely threaded. Finger tight first


Definitely. Thanks for pointing it out!


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## TheVarix (Apr 3, 2013)

Regarding bleeding sequence, I've had a good look at the Bentley manual and on section 03-30 it specifies the bleeding sequence for cars with manual transmission:










Which seems to be the standard sequence.


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## Hoggy (May 8, 2002)

TheVarix said:


> Regarding bleeding sequence, I've had a good look at the Bentley manual and on section 03-30 it specifies the bleeding sequence for cars with manual transmission:
> 
> 
> 
> ...


Hi, On Bentley pages 47.3/4/5 it states the opposite sequence  :? 
M/C on right drive car on the right.
Hoggy.


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## TheVarix (Apr 3, 2013)

Thanks, Hoggy. Contradictory info. Hmm...


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## droopsnoot (Sep 5, 2002)

Hoggy said:


> Hi, Never known the OEM rear brake hoses to be any different from the front. Never had a prob clamping hoses in the past, although usually always new hoses.
> Hoggy.


I've only swapped one caliper, nearside rear, and I clamped the hose and haven't had any problems to my knowledge - it passes the brake test. That was with a proper clamp, done at my mate's workshop under some supervision as I'm still reasonably nervous working on the TT.


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## blackshaddow (Jan 5, 2016)

Hy friends 
Just a quick one
To do the bleeding do i realy need a second person to press the brake pedal in the car ?
Or i can just keep the brake fluid can full and loose the bleeding niple and pres few times breke pedal and then come back to the bleeding niple and tight it?
Thank you fot diy is verry helpfull
Cheers


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## David C (Apr 15, 2013)

blackshaddow said:


> Hy friends
> Just a quick one
> To do the bleeding do i realy need a second person to press the brake pedal in the car ?
> Or i can just keep the brake fluid can full and loose the bleeding niple and pres few times breke pedal and then come back to the bleeding niple and tight it?
> ...


To do it properly you need a 2nd person to pump the pedal.
Unless you use a vacuum tool to suck the brake fluid from the bleed nipple or a pressure system into the reservoir.


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## blackshaddow (Jan 5, 2016)

Thank's for the reply 
2nd person method was the method i was always using but i thought you peope use another method
Aniway i did it last night,bleeded the breake MC and now i have a proper breake 
Thank you for help


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## westo3 (Jan 15, 2011)

Excellent thread. Very useful info and pics. Have now book marked it


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## traydhat (Jun 19, 2017)

Thanks for the write up.

I had so much trouble bleeding the master cylinder - just couldn't get a spanner and a bleed tube on the bleed valves.

I resorted to pressurising with an easibleed system, covering the engine bay in rags and the floor with cardboard and releasing the bleed valve with a 7 mm socket, did that a couple of times for each of the 2 bleed valves. It worked perfectly and the brakes are as good as they ever were. Bit messy but soon cleaned up.

Cheers


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## westo3 (Jan 15, 2011)

Excellent thread. Have booked marked it as I need to renew my rear discs and thought I would have a go at painting the calipers. It is going to be so much easier with such clear photos and instructions followed by tips. Many thanks.


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## MartynJP (Mar 8, 2017)

Hi Guys,

Just had my wife's Mk1 fail the MOT because the rear brakes were binding....probably because its been stood for months. So, as the binding hadn't done too many favours for the discs and pads, I got some new parts and set about fitting them. All going ok until I find I cannot get the piston to retract (using a wind in tool) on the near side unit. Putting a spanner on the handbrake bolt at the rear of the caliper made the piston come out, but no way on Earth could I shift the blighter back in!

So, as new calipers are around £85 each, can anyone tell me if I'm doing something incorrect or is it quite likely the unit is seized??

Cheers, Martyn.


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## David C (Apr 15, 2013)

It not winding back is the same reason they were binding.
Seized internals.

My left rear was the same.
I replaced the pair.


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## MartynJP (Mar 8, 2017)

David C said:


> It not winding back is the same reason they were binding.
> Seized internals.
> 
> My left rear was the same.
> I replaced the pair.


Cheers David.....my gut feeling was that it was probably seized but just thought I'd put it out there to see if I was doing something dopey!

Martyn.


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## David C (Apr 15, 2013)

MartynJP said:


> David C said:
> 
> 
> > It not winding back is the same reason they were binding.
> ...


I managed to wrench mine in with HUGE effort for one change, but was constantly squeaking soon after, it just delayed the inevitable caliper replacement. Wish I'd done it sooner.

New freely moving calipers wind in sooooo easily...!


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## StuartDB (Feb 10, 2018)

I simply serviced my seized rear calipers with new seals and poished the pistons - I think it was about £14 for both sides - to get them out I needed to action the handbrake mechanism over and over.


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## MartynJP (Mar 8, 2017)

StuartDB said:


> I simply serviced my seized rear calipers with new seals and poished the pistons - I think it was about £14 for both sides - to get them out I needed to action the handbrake mechanism over and over.


Thanks Stuart....I did think about new seals, but I am concerned that the amount of force I think will be needed to get the piston out might indicate how corroded it is, and the polishing might be a long task! To be fair, the car has only done a few hundred miles since last year's MOT and I bent the wind out tool bar already trying to shift the damn piston! Plus I have better things to do than sit on the drive playing around with my wife's old TT lol!


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## MartynJP (Mar 8, 2017)

Just to conclude, I did go for new calipers and they went on very easily as the piston was right back out of the way. After bleeding the hydraulics, the pads self-adjusted by pumping the brake pedal a few times and everything worked well.

So, I tried....really tried with a lot of force.....to move one of the stuck pistons and when I eventually got one out it was pitted and corroded beyond polishing.....incidentally, the disc was blue through the heat the seized caliper had caused so I guess the moral of the story is don't let your TT sit around for a long time without using it or the rear brake caliper pistons will weld themselves to the cylinders and cause you grief!! Thanks for the help guys


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## NickA555 (Mar 12, 2018)

TheVarix said:


> Here are 3 pics: one of the fitting of the hand brake cable and 2 of the finished product:


I'm going to be replacing the rear calipers on my 225 soon and have a question for somebody. In the above picture, where the banjo bolt and brake line connect, do I have to remove the 'bracket' from the old caliper and transfer it over to the new caliper? (If you're unsure what I mean, look at the picture on the left where the caliper is red and this 'bracket' where the line connects looks old and dirty.

Hopefully that makes sense to somebody?

Thanks in advance

Nick


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## David C (Apr 15, 2013)

NickA555 said:


> I'm going to be replacing the rear calipers on my 225 soon and have a question for somebody. In the above picture, where the banjo bolt and brake line connect, do I have to remove the 'bracket' from the old caliper and transfer it over to the new caliper? (If you're unsure what I mean, look at the picture on the left where the caliper is red and this 'bracket' where the line connects looks old and dirty.
> 
> Hopefully that makes sense to somebody?
> 
> ...


The bit you're looking at is part of the rear brake pipe.


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## NickA555 (Mar 12, 2018)

David C said:


> NickA555 said:
> 
> 
> > I'm going to be replacing the rear calipers on my 225 soon and have a question for somebody. In the above picture, where the banjo bolt and brake line connect, do I have to remove the 'bracket' from the old caliper and transfer it over to the new caliper? (If you're unsure what I mean, look at the picture on the left where the caliper is red and this 'bracket' where the line connects looks old and dirty.
> ...


Thanks David, I assume it should detach from the old caliper then? (I took my caliper off at the weekend and that part felt like it didn't want to move anywhere)

Cheers


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## TTorBust (Mar 8, 2018)

There's a big company called Bigg Red that'll service (with new pistons/seals etc) and repaint paint 2 calipers for £125. You could probably do it yourself for half that so your spending about £60 for a professional to do the job.
Anyone have experience of the company?


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## David C (Apr 15, 2013)

NickA555 said:


> David C said:
> 
> 
> > NickA555 said:
> ...


You just undo the banjo bolt and it comes away with the rest of the pipe (you don't disconnect the pipe from that block). There are copper "O" rings each side of it and you'll need replacements.


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## imartyn (Aug 31, 2015)

This what you will get with new calipers.....


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## westo3 (Jan 15, 2011)

Great pictures and description. I assume the 3.2 is the same prceedure


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## David C (Apr 15, 2013)

westo3 said:


> Great pictures and description. I assume the 3.2 is the same procedure?


Yes, the 3.2V6 uses the same rear brakes as the 225 1.8T


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## NickA555 (Mar 12, 2018)

David C said:


> You just undo the banjo bolt and it comes away with the rest of the pipe (you don't disconnect the pipe from that block). There are copper "O" rings each side of it and you'll need replacements.


Cheers David. I had to remove the block with a few 'taps' with my persuasion tool as it was stuck fast and going nowhere (And that was the reason why I thought it was actually part of the caliper)


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## WaynoTTV6 (Apr 9, 2015)

To get the to the MC, just unbolt and remove strut brace and the support bracket above the reservoir.

13mm socket from memory.

Frees up so much more space, to get to the nipples on the master.

Definately recommend the sealey pressure bleeder too. A few quid, but so worth it. Just grease the inside of the plastic screw lids with a smear of clear grease and no tiny air leaks will appear.

Sent from my SM-G935F using Tapatalk


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## Farseer (Dec 3, 2018)

Lads, how would one bleed the MC if there were no bleed nipples present?

Is the only option to bench bleed them? In that case, I think I'll get used to a spongy brake.

OR, would the bleeding actually take place from the nipple at the slave cylinder? In the case of an absence of bleed nipples on the MC itself, I guess a good option would be is to try vacuum bleeding the clutch.


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## TTorBust (Mar 8, 2018)

The obvious question would be where have your nipples gone? If it's not to personal.


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## Farseer (Dec 3, 2018)

TTorBust said:


> The obvious question would be where have your nipples gone? If it's not to personal.


Hah! Unfortunately, I have no idea...


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## thehof2012 (Jun 4, 2020)

I used this how-to when I replaced my left rear caliper, and this was SO helpful. Really appreciate you putting it together, saved me a decent hunk of change in the process.


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