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View Full Version : DIY brake change - what I did/lessons learned



Thehead
08-10-2021, 03:12 PM
Hey guys, I just finished replacing my oem rotors and pads with GiroDisc rotors and pads. I figured I'd report in and share my experience to help other people since I couldn't find a whole lot of information when I was doing it, If anyone has more information to add, feel free to post below! This isn't a step by step, I'm doing this after the fact, so I may miss things. If you aren't comfortable doing this yourself, please have a professional do it, your safety isn't worth the risk. On my 2018 RS5, the wear sensors are only on the Driver's side for the front and the passenger side for the rear on the inside brake pad. The Girodisc pads come with embedded sensor only for the front brake pads, 2 have sensors and 2 do not. The front pads do seem to be directional, but are not labeled so be sure to pay attention when removing the stock pads.

I started off with the rears, first thing (after getting the car off the ground and taking the wheels off) was use my OBD Eleven to open the rear brakes, following the instructions on the app. You will be able to hear it, be sure to hit the check mark to actually make the car open the brakes. Next thing I did was disconnect the actuators to make sure they weren't going to close for some reason. The rest of the rears is a standard brake job.

Caliper mount bolt spec (the 18mm bolt) is 100Nm + 90 degrees , use new bolt.
Caliper bolt spec (the 13mm bolt with 17mm wrench) is 35Nm, use new bolt.

Tools for the rear:
You will need a Torx T30 bit to remove the screw that holds the rotor to the hub.
13mm socket for the caliper bolts
17mm wrench (may have to be ground down to be thinned) to hold the nut between the caliper bracket and the caliper
18mm socket for the caliper mount (you may be able to just take off the caliper mount with caliper attached to avoid having to grind down a wrench like I did)

Now for the fronts, these were a bit tricky for me since I've never done brakes on a performance car like this before.

Some things I noticed for the fronts:
You don't need to remove the bolts on the caliper that require a special 7 point socket (I saw some "tips" that said you can get by with hammering on a 1/2" 12 point socket onto it, don't do it) You can just reach around to the back and take the whole bracket off with a 21mm socket. Be extra careful with the brake lines since these are hard lined from the suspension arm to the caliper, I wanted to take the mount for the brake line off but they required a special 18 point star bit or something like that. This is where it's helpful if you have someone that can hold the caliper for you while you change out the rotor and pads since you can't just zip tie them out of the way like you can for the rears.

With the caliper held carefully just out of the way, remove the old rotor. remove the old brake pads paying attention with the orientation of the wear surface so you can match with your new ones. Spread the pistons to allow the new thicker pads to be able to fit onto the rotor in whatever method you prefer. On the driver's side with the sensor, you have to remove the spring in order to pull that sensor line out (only the one spring, you do not need to remove both. The easiest way is to push it from the outside in (or tap it with something to knock it inwards) pay attention to how it is oriented so you know how it goes back in. You cannot install that spring from the outside of the caliper it needs to be tapped back in from the inside of the caliper, be sure to send the new sensor through before re-installing the spring. With the spring re-installed insert the new brake pads so they are aligned in their slots. To fully seat them I did one at a time, using a small pick tool or maybe even a small screwdriver in the "wings" of the springs on the side you're working on. You'll need two, one for the top and one for the bottom and gently pull the wings back just enough to allow you to install the brake pad fully, this is why having an extra person is helpful. You could try forcing it to fully seat with a pad spreader, that's what the service manual seems to tell you to do, but I didn't want to risk damaging my new pads. Caliper bolt spec is 200Nm, replace with new bolt

Tools needed for the fronts:
You will need a Torx T30 bit to remove the screw that holds the rotor to the hub.
21mm socket for caliper bolts
2 pointy tools for spreading the "wings" of the brake pad springs

If anyone needs pictures in the next 12 hours I should be able to do it, after that I won't easily have access to detailed shots. I didn't know I was going to be doing a sort of a write up, otherwise I would've taken more pictures along the way. I'm just hoping this will help someone.

https://i.imgur.com/aqfnCEX.jpg

ywang98
08-10-2021, 04:45 PM
Thanks for the posting. Do you happen to have the torque settings handy?

In the old Brembo's on Porsche's and my wife's old Touareg TDI, it was super easy to change the front brakes as the pads were held by a pin and a plate spring. Just remove the pin and the spring plate, pull out the pads, put new pads back in. But these new calipers all need to be removed completely before you can get to the pads.

Thehead
08-10-2021, 05:43 PM
Thanks for the posting. Do you happen to have the torque settings handy?

In the old Brembo's on Porsche's and my wife's old Touareg TDI, it was super easy to change the front brakes as the pads were held by a pin and a plate spring. Just remove the pin and the spring plate, pull out the pads, put new pads back in. But these new calipers all need to be removed completely before you can get to the pads.

Front caliper mount bolts (21mm) are 200 NM, rear caliper mount bolts (18mm) are 100 Nm +90°, rear caliper bolts (13mm) are 35Nm. Both are supposed to be replaced after removing. Yeah, I wish these pads were that easy, I think the RS3's use that style.

Bullhorn717
08-12-2021, 01:50 AM
Thanks for the post. I just got a quickjack TL5000 and definitely will be useful if I need new brakes in the future! How many miles did your original pads last for you?


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Thehead
08-12-2021, 03:31 AM
Thanks for the post. I just got a quickjack TL5000 and definitely will be useful if I need new brakes in the future! How many miles did your original pads last for you?


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I'm not exactly sure, I'd assume that they're factory. I bought the car with 20k miles, and it's now around 30k. The problem was actually horrible rust. I had a couple long work trips during the spring, so I had a time where my car sat in the parking garage for a bit over 2 months. Apparently that was enough to ruin the rotors. I drove 2k miles and it still didn't clear off completely. The functionality was fine, but it the pedal feel was awful and would vibrate the car a bit. The dealer wanted $3k to replace the fronts, so I figured I'd just upgrade and do the whole thing for $3k aftermarket.

I'll attach a picture of the factory rotors and pads a bit later today.

ToroTheShibe
08-12-2021, 11:33 AM
How’s the bite/dust/noise on the giro?

Thehead
08-12-2021, 11:50 AM
How’s the bite/dust/noise on the giro?

The bite so far seems less agressive than stock, but I've only run them for 50 miles so far, and 25 miles of that was just bedding them in. Too early to tell for dust, but supposedly it's less than stock. No noise other than a bit of a squeek at slow complete stops, but I had that with stock too. I'll give an update once I get some more miles on them when they're good and broken in.

ToroTheShibe
08-12-2021, 09:42 PM
The bite so far seems less agressive than stock, but I've only run them for 50 miles so far, and 25 miles of that was just bedding them in. Too early to tell for dust, but supposedly it's less than stock. No noise other than a bit of a squeek at slow complete stops, but I had that with stock too. I'll give an update once I get some more miles on them when they're good and broken in.

Looking forward to that! I actually didn't mind the factory dust too much since my wheels are ceramic coated. Most annoying thing was braking in the city. SOOOO LOUD but thats the price you have to pay for bite.

Bullhorn717
08-25-2021, 04:45 AM
Is the brake bleeding process pretty straight forward? I’m assuming these big front calipers have inner and outer bleeding screws.


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Thehead
08-26-2021, 09:04 AM
Is the brake bleeding process pretty straight forward? I’m assuming these big front calipers have inner and outer bleeding screws.


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I didn't need to bleed the brakes, so unfortunately I don't have any info for you.

Unrelated to above, I now have some miles on the brakes. I'm happy with them so far with my use case being a factory replacement, they feel just like oem. Same low speed braking creaks for me (<5mph coming to a slow stop). I haven't done any agressive braking yet though, but I may not be the best person to judge that since I don't track this car. Too soon to tell on if there is any difference on brake dust.