Help with rear brake caliper question

[chroniclesofcf]

Hi guys,

1.4TSi 2018 SC FR with electronic brake.

Rear drivers side caliper was sticking. Took everything apart to find the pads were non existent. Thought the pad and rotor would be fusing. Did pads and rotors all round and thought it might have been the fix. Problem came back.

Had a look again today, greased everything up, made sure the caliper piston was moving. While it’s hard to push back in by hand (it should be right?) it came out no problem. Put everything back together, made sure it was bled which wasn’t needed, made sure brake fluid reservoir wasn’t over filled, but still have the same caliper sticking.

however, while the electronic brake service option is open, the car rolls fine/better. So I believe it’s the actual brake servo. I did get a message of “brake servo restricted” when it was opened via Carista, but at the time i thought that might have just been an error thrown due to it being opened.

im now thinking of changing the caliper along with the motor, but can not for the life of me find a 253mm caliper with the brake servo. Is it possible that the 272mm one fits? I can find loads of those.

Any help would be appreciated.

 

[Cainy1989]

have a look for ones from the Audi A3 8V they had an electric handbrake even on the base SE so will have the motor attached and be the correct size. if you get the bigger calliper you'll have to do both sides and the discs and pads

 

[SuperV8]

Are you sure you have 253mm discs?
I thought all EPB rear brakes were the 272 disc.
If you IM me your reg I can confirm.

 

[chroniclesofcf]

Are you sure you have 253mm discs?
I thought all EPB rear brakes were the 272 disc.
If you IM me your reg I can confirm.

Well, if that’s the case, I’ll be ecstatic. 272mm caliper are in abundance and fairly cheap too.

I did just do the brakes and pads as mentioned, and I can’t remember why but I was convinced into thinking I had the 253mm, so bought discs accordingly. The caliper that was stuck had maybe 1/10th of the top of the pad not being eroded/used, so there was a massive step on the pad from it being stuck on.

 

[SuperV8]

I can confirm your rear disc OEM is 5Q0615601D which is 272X10MM

If you have fitted 253 obviously they are too small - and the pads with overhang the disc - but also the 253 disc is slightly taller than the 272 meaning it can rub on the caliper carrier.

 

[chroniclesofcf]

I can confirm your rear disc OEM is 5Q0615601D which is 272X10MM

If you have fitted 253 obviously they are too small - and the pads with overhang the disc - but also the 253 disc is slightly taller than the 272 meaning it can rub on the caliper carrier.

The bracket was touching the rotor, ever do slightly. I thought it might have been down to build up overtime, so ground it away 🫢

so this **** up is now a whole new setup round back. Disc, pad, caliper with servo and carrier. Superb

I appreciate the clarification! Life saver.

 

[SuperV8]

No worries.
I have had a caliper carrier bind on a disc before - due to corrosion of the knuckle so it can be a thing!

Which part of the caliper carrier did you grind away?
The mounting part where it bolts on - or the part where the pads sit on?
If the part where the pads sit - you might get away with using them.
If the part where it bolts on I would say you'd defo need new carriers.

 

[chroniclesofcf]

No worries.
I have had a caliper carrier bind on a disc before - due to corrosion of the knuckle so it can be a thing!

Which part of the caliper carrier did you grind away?
The mounting part where it bolts on - or the part where the pads sit on?
If the part where the pads sit - you might get away with using them.
If the part where it bolts on I would say you'd defo need new carriers.

It would have been pad side I was grinding away.

i might just replace the carrier anyway as it’s not that expensive and would look odd with a new caliper and old carrier.

So, new discs (272mm!), new set of pads, one caliper with servo and one carrier. Jeez Louise. Least I know now.