MP4.2+6.0

I think you are referring to ceramic pads. Those are common these days; some work well and others are kind of like greased teflon mediocrity. (Current formulation of) EBC Reds I use are ceramic based as one of many examples.

But most of the post is referring to full ceramic brakes, including particularly the rotors made of ceramic powder material. That's an entirely different animal than steel/cast iron based conventional rotor systems. The front caliper on them is a pretty classic many piston Brembo, while the rear caliper appears to be standard D3 with only a larger diameter mounting bracket. The rotors are the super pricy part, though the pads aren't cheap nor easily available except via dealers. They are also inherently two piece rotor and hat set ups, so the hat area being alloy takes out yet several more pounds of weight. On the fronts you drop a huge 20+ pounds of weight in just the overall rotor on each side (in W12/S8 sizing). In the rear the rotor size actually steps up somewhat, and the overall weight delta is minor compared to the front change.

Audi first introduced it as a very high end option on the Euro D3 circa 2005 or 6. After that it spread to the R8, using basically the same parts in front, but thicker rotors and a different parking brake set up in rear.

MP4.2+6.0

You are in Europe where the ceramic application can be found for the D3, but from here in the USA, yes the pads seem very expensive and hard to find. The front pads apparently interchange with R8s with the 380mm set up, so you can look for those too. Rears seem to be a unique (to D3) part. But the rear caliper also appears to be standard D3 with a bigger mounting bracket--perhaps driven by the unusual-in-its-day rear electric parking brake unit need. Thus, you might check on Euro boards and see if anyone is successfully using "conventional" pads in the rear, particularly some ceramic compound.

The rotors are tested for wear by both weight and thickness. Audi said they could run up to 300,000 km IIRC. Typically the wear is very hard to even see, so they need to be mic'ed. Also why the weight spec is included. Because of the hardness, the wear is very slow. BUT, the spec is also very tight, allowing only fractions of a mm total wear instead of up to 3mm (front) like on the S8/W12 385mm conventional set up. I have the wear spec somewhere if you need it.

If you look BTW, the thickness AND weight are both shown on the ceramic rotor hats. So is the manufacturing date. If yours are early BTW, they may have been recalled. Apparently all the early ones got called back--D3's and R8's--to replace the rotor hat to disc ring bolts due to corrosion. The bolts are not sold as a piece part AFAIK, though there seem to be aftermarket suppliers now of the ceramic rings that come with replacement bolts. From what I can tell on the boards I read at one point, it sounds like in at least some cases people may have ended up with new complete rotors in the recall. You might want to check and see if yours are on the recall list, and if it got done. If you look at your rotor manufacture date and compare it to your D3 build date, that will be another pretty good clue.

MP4.2+6.0

I was doing some surfing about brakes in the last few days. I have reconfirmed a variety of ways now that the 380mm R8 ceramic brake set up in front is the same as the Euro optional D3 ceramic set up, including a lot of the parts--pads, rotors, underlying caliper (as distinct from the mounting bracket), sensors, etc. In turn if you look at pad fitments for the R8 ceramic option (in the 380 mm size), you can find a variety of alternatives. The OE pads seem to be Pagids, which are the expensive ones from listings I found. Centrics are listed very inexpensively, and Delphi , TRW and Ferodo all much less than the OE's. Since they are Brembo calipers, I think there is a Brembo fitment too, but have not tracked that down completely. Other than the Pagids, they actually price in the same range as many conventional aftermarket pads for the 385mm conventional brake set up--at least in $ terms and US availability. The compound is conventional but with a bit more metal content per some Audi documentation.

The separate wear sensors are quite expensive, but it looks like there may be work arounds and aftermarket choices there, especially if you can get back to the Brembo part #. I suspect sensors from the Cayenne/Touareg/Q7 conventional Brembo fitment may be essentially the same, but available for much less and from aftermarket.

Galco

So do these findings support and suggest a ceramic brake upgrade is possible and in your future??? That would be quite interesting, IMO.

gedis080

for example, what i have on my S8:
front brake pads for ceramic brake discs TRW GDB1660 - ~55USD
rear brake pads for ceramic brake discs FERODO FDB1655 - ~45USD

if you want to get rid of ceramic brakes or other way around then you will have to change wheel bearing housings and calipers as well.

NightOwl

The only change in wheel bearing housing as I can find in my sources for the D3, is during 2004 model year, nothing different for those fitted with ceramic brake discs. Do you have part numbers to confirm?

MP4.2+6.0

I don't think there is any change to the wheel bearing, nor does that really make any sense to me. If the rotor offset is different, then you get into hub changes, which in turn essentially mean a new bearing, but that is different. I don't think there is any hub change front or back, and thus no bearing change, and no hub change I am aware of either.

Yes, the front caliper is clearly different, but that is part of the point. The ceramic calipers are true fixed Brembo set ups (i.e. pistons on both sides). The rears actually seem pretty D3 stock with a different bracket to get to 356mm, though the rotors are a little thicker. D4 rears are also 356mm on the V8 motor ones, but having looked at the caliper brackets there, the pads are essentially the same size but the mounting ears have a slightly different angle cut to them, and use a different anti rattle shim part #. All suggests to me that while really close, the rears end up needing a caliper change too even though the true difference is minor. But in the rear, given essentially same caliper and a rotor upsizing in ceramic, most of the weight savings (both unsprung and rotational mass too) as part of the conversion rationale is up front. Still looking into details, but on just the front rotors it is approx. 20 pounds. I suspect from my Q5 to RS5 swap that used eight piston Brembos w/ semi floating conventional rotors, the calipers may yield at least several more pounds--the big cast iron mounting bracket becomes a very small Brembo auxiliary bracket to the alloy caliper.

Where hub changes do tend to come up is with RS set ups in the back. Thus, the C5 2003 RS6 uses a 335mm rotor just like the W12 and D3 S8, but the RS6 rotor is semi floating and somewhat lighter given the alloy center hat. But there is approx 5mm offset difference between the two, so in practice you have to do a hub change too. The offset change is on the "wrong" side I think, so you also can't just spacer/washer the caliper over to make it up. There is a similar issue with RS5 rear brakes too, which makes them not easily retrofit to an A4/S4/A5/S5/Q5 without a hub swap. Not sure on the C6 RS6 to D3 conversion scenarios. Yet again the other day in researching and e mailing, it is really hard to assemble a C6 RS6 front set up at acceptable prices and get it to North America. Weirdly when I typed in some part numbers, ecstuning.com ( a pretty good aftermarket Audi parts source in USA) is listing a variety of the part #'s; the brakes are used by some tuner types apparently like TT/TTRS set ups so there may be some aftermarket business there.

Various other changes to like molded in front pad sensors become a separate part, but still plug and play at the plug in point. Heat/water shields change too and can't be found in U.S.; here I suspect the 385mm ones for the W12 and S8 may still be fine in front, and there is a D4 356mm one for the back that looks like it has the same bolt points and is (uncharacteristically) inexpensive. As mentioned above, the rear calipers themselves remain Audi single piston floating basic per the last 15 years or so design, just with the electro parking brake add on.

MP4.2+6.0

Focused on the front so far. Rear trickier w/ the parking brake so it isn't straight R8 cross over, and the ceramic rotors are also a thinner size than Audi seemed to settle on later. Rational cost wise, the hard part is finding the big bucks (Euro) rotors at any sort of remotely justifiable price for an older vehicle--let alone a new one! There is also some beaten up junk out there that variously looks way too worn/abused, so that also has to be passed over even if pricing is better.

At least for the fronts, there is also some donor availability from Euro W12 Phaetons. In the used parts arena with (occasional) somewhat rational pricing if you look long and hard enough and can deal w/ Ebay Germany there is more front availability than rears. Still playing with C5 RS6 rotors in the back using my stock D3 W12/S8 calipers, but getting hung up on the rotor hat offset per the other reply I made today in this thread. Need to get home and look at mine more, but I don't think it is solvable w/ out a hub change...not happening. Some deal with that in the similar RS5 conversion by putting 5mm spacers behind the rotor, but that doesn't seem like a great idea mechanically to me at all.

Stay tuned. Will take a while to assemble the necessary components. Finding the direct R8 to D3 front pad equivalency was important for maintenance/parts availability in future, given pads are the only practical wear/replacement item (besides sensors if pads run too long). Then once I found the other OES/quality third party pads listings in front for less than I pay now for dealer or EBC, that was good. I backed away from the rear ideas a few months ago when I couldn't find OE pads in US (or even the Euro EBay's), but now have found the OES/quality third party pad listings for the rear as well. Various of the pads (front and rear) are even findable surprisingly cheaply via commodity US sites like rockauto.com, and also pretty easily on EBay here or via Europe once you get back to the vendor part numbers (TRW, Bosch, sometimes Brembo, ATE, Pagid [the OES pricy ones], etc.).

Brozee

I believe the new ceramic brakes have to be coded via VCDS as well. Ceramic brakes generally require the car to frequently and automatically apply the brakes so that the rotors are always at the desired operating temperature. Ceramic brakes/rotors do not perform well cold, hence the coding necessary. I know it's the same way on some ceramic equipped RS5's and RS7's.

mishar

That would really increase fuel consumption, not to mention comfort. Fortunately they fixed that problem by choosing different materials.