Ceramic brake retrofit need a bit of help please

[Adrian E]

Julian - have you got all the info on how Audi recommend inspecting/weighing the discs to ensure they're serviceable?

I imagine it's in one of the tech dump files, but if not I can probably find it in ElsaWin

[Julian Thompson]

Evening gentlemen, hope we are all having a good weekend.

So I bought the four calipers, discs, backings and abs unit for £2000 and then I’ve had to pay £500 for the replacement disc.

I have noticed that Rebrake and Redisc both offer services to recondition discs, at around £1600 per disc. I don’t think they could necessarily sort out my damaged one though as it’s pretty heavily gouged in the middle. So I’m going to run the discs and see what they’re like. Later, if needed, I’m prepared to send them away to be fettled.

My thinking - could be totally wrong - is that I think it’s pretty unlikely that the rears will have been put under any significant load with the D3 S8 being all nose. Also, since we have speed limits here I can’t see the brakes having being exposed to too many 150mph stops, and I don’t expect an S8 to have too many track miles under its belt either, which is where CCB’s are known to wear significantly faster than one would like. So hopefully they should be in reasonable shape - they certainly look it. Obviously I haven’t received the fourth disc yet but that’s reputed to be very low mileage.

It would be great to get the info on wear checking, so I can verify the position before we begin.

I’ve obtained some forged wheels too which when combined with these brakes should lower the unsprung and rotating mass nicely…

[steamship]

Originally Posted by Julian Thompson

It would be great to get the info on wear checking, so I can verify the position before we begin.

Check out the following PDF from the D3 Tech Dump thread:

17-Service Manual Brake system.pdf

Technical info at the start and details for fitting them in other section.

[Julian Thompson]

Super helpful thanks - I’m well within tolerances from every perspective so looking good. Calipers need a good bit of attention as they look like something that came up with the titanic at the moment. (See pic)

What I can’t work out is why they say not to detach the alloy centre. As soon as I read that I obviously detached it on my “spare” disc to see what the fuss is about. I tested the torque on the fasteners before I undid them - 6nm to move the nuts so I reckon 5nm tightening torque, and the alloy bell auto centres due to the sliders. I was considering putting the discs in my ultrasonic cleaner but I need to work out what solution to use. I’m guessing something gently alkaline.

[homer simpson]

They don't look too bad. A full refurb (seals and paint) and a new set of the springs/shims will make them new. The shims are still available from Audi/TPS for around £70 a set

[Julian Thompson]

Great - can I get seal kits for them do you think?

Also, it seems that the original seller isn’t a man of his word and has let me down on the abs unit and the 4 disc guards. Can anyone here help me with the part numbers for the 4 guards? I know the abs unit, obviously. Very frustrating.

[steamship]

Originally Posted by Julian Thompson

Can anyone here help me with the part numbers for the 4 guards?

Front left - 4E0615311L or 4E0615311M
Front right - 4E0615312L or 4E0615312M
Rear left - 4E0615611G
Rear right - 4E0615612G

[Julian Thompson]

Ahh thanks you’re an absolute legend.

[Julian Thompson]

Hmm these seem to be unobtainium. I’m wondering if the parts off the w12 might be usable as that had big discs? What do you think guys? And if so what about part numbers on those?

[steamship]

Originally Posted by Julian Thompson

Hmm these seem to be unobtainium. I’m wondering if the parts off the w12 might be usable as that had big discs? What do you think guys? And if so what about part numbers on those?

Can't give you an answer, but I can give you the part numbers and figures. I've attached images of the ceramic disks and steel disks. Don't know if these are 100% accurate, but in the image of the front ceramics, the guard appears to have like a large lip at the end.

The front ceramics are 380mm, the steel ones are either 360mm or 385mm. Part numbers for the larger front guards are 4E0615311H (left) and 4E0615312H (right).

The rear ceramics are 356mm, the steel ones all use the same part number regardless of size. Part numbers are 4E4615611A (left) and 4E4615612A (right).

Having written all that, I just decided to check out a site I've used before and they are showing all the four guards for the ceramics listed in my previous post. Some parts are listed as 'special procurement Audi Tradition' but I think it only shows up during the checkout process:

https://originalteilemarkt.de/