RS6 C5 Phaeton 6.0 W12 Rear Disc Brake Rotor Installation

[mrjrd]

Hi all,

Just a quick knowledge share on how to avoid the Audi main dealer prices for replacement RS6 rear discs.

My rear brakes badly needed replacing as my pad had corroded and left metal on metal under braking, so I started to investigate what my options were.
Having driven BMW's in the past, I was quite shocked to see how little alternatives there were to RS6 brake parts. My Z3M Coupe's parts were nearly all from the E46 BMW M3 and surprisingly reasonable on the wallet.

As the rear brakes were the first work I had to carry out on the car, I was shocked to see that discs were starting at £300 each from main dealer. Maybe this was less elsewhere from garages that I didn't manage to find, however I was sure there must be alternatives.

I saw on this forum and others that people had managed to fit the Volkswagen Phaeton 6.0 W12 rear discs onto their RS6 and I was intrigued to see if I could do the same and save many £££'s.

So I went out and bought the following,

VW Phaeton 6.0 W12 Rear Discs
EBC Standard Brake Disc
Vented - 5 Bolt Hole - Diameter 335mm - Height 42mm - Thickness 22mm
Model No - D1418

RS6 Yellowstuff Rear Pads
Model No - DP41470R

I saw on a forum that someone mentioned that I need to put washers on to make the disc fit, but for the life of me could not work out where.

So the disc went on and immediately I noticed that there was a problem.
The drum on the disc is shallower than the Audi part and therefore does not sit so deep into the car. I then worked out this is where my washer comes into play.
I took the caliper carrier bolts out with an allen key and put 2x spring washers (2mmx15mm) on the inside of the car and then put the bolt back in. This sufficiently brought the caliper out away from the car to center around the disc again.
My only worry after this was whether the caliper would now touch the wheel, however upon fitment this was not a problem as there lots of clearance.

And that was that. What went from being an £800 job turned into a sub £200 cost.
The cars bite feels strong and true under breaking and for everyday driving they seem very satisfactory. Most happy!

I have linked some pictures below for reference. Please excuse the oily mess, a leaky DRC is being replaced next week. I have the PSS9's in my hand. Oh they are beautiful and I'm itching to fit them.



Jon
RS6 C5 2002


Washer Position


Hub Depth


Phaeton & RS6 Disc Comparison


EBC Phaeton 6.0 W12 Disc


Removed RS6 Disc (the good side!)


Yellowstuff Pads for RS6

[HYFR]

well done ... that was me that did the phaeton rears !

[mrmule]

do you think you could get away with slightly larger diameter washers, purely based on your first photo?

[mrmule]

Oh and are you running stock wheels? Curious about 'rubbage' (more like 'grindage') on C6 20' wheels...

[mrjrd]

@ mrmule
The diameter of the washers will not be a problem (nothing OTT), the depth has to be pretty precise though. By no means did I put any science to this, I just lucked out with 2x spring washers with their combined depth.
My wheels are stock 19's and clear nicely from the grindage, rubbage, and all things touch'age.

@aka_dk
Thanks buddy, who dares wins!

[mrmule]

@ mrmule
The diameter of the washers will not be a problem (nothing OTT), the depth has to be pretty precise though. By no means did I put any science to this, I just lucked out with 2x spring washers with their combined depth.
My wheels are stock 19's and clear nicely from the grindage, rubbage, and all things touch'age.

Pukka; might go for some 25mms.

Just ordered everything! Thanks!

[monoi]

You did not use longer bolts to compensate for the reduced depth they will reach because of the washers?

I don't think it is a problem as it is only the rears, but I wonder what a Mot or insurance engineer could say.

[grizz]

The disc is all steel so weigh more ..All the rs's have a alloy centre to keep weight down.. It's a cheap fix but not ideal.

[Fizmo100]

Has anyone weighed the two side by side? It'd be interesting to know how much extra weight the Phaeton disks add.

[mrmule]

Seeing as I dont go hurtling around at 200mph most of the time, plus it being a 77.5% saving in cost; I can handle a few extra grams for that. Given, its unsprung mass which is worse, but an extra £600+? Easy decision for me.

[HYFR]

That's how I felt ... Yes they are heavier, yes they are not drilled ... But so much more VFM

[Daveperc]

Seeing as I dont go hurtling around at 200mph most of the time

That's not the issue - it's every time you go over a pot hole etc the suspension damping system (DRC or coily) has to work harder to damp out the motion of the wheel. Probably not a big deal, but even a few percent increase in unsprung weight can be noticeable.

Dave

[mrmule]

Seeing as I dont go hurtling around at 200mph most of the time

That's not the issue - it's every time you go over a pot hole etc the suspension damping system (DRC or coily) has to work harder to damp out the motion of the wheel. Probably not a big deal, but even a few percent increase in unsprung weight can be noticeable.

Dave

I guess in my mind, that part of my comment was more to do with them not being cross drilled.

[mrjrd]

@Daveperc
I held both discs at the same time in either hand and could not feel a difference. I would be quite surprised if the small amount of extra weight could be related to extra coilover\DRC wear.
For the people who install larger 20 inch rims (if possible?) or uprated larger discs upgrades on their RS6's, do they notice more DRC failure or coilover trouble than others because of the weight?
I will call EBC and ask if they can give me the weight of the Phaeton discs and then I will compare against the used one I have here.

@Mrmule
My rears were not cross drilled to start with so this was a no brainer for me. I would be reluctant to buy cheaper cross drilled discs as I have heard stories of the drill holes being a point of weakness and cracking.

@Monoi
No the extra length bolts were not used. I am looking at doing my PSS9 install tomorrow so will see if this is an issue. I cant remember how much extra thread was left when tightening, however I am almost certain this was not low as I would have noticed with me being a responsible gent an'all.

[mrmule]

I wanted to add a little more to this thread if I may: I fitted the phaeton discs and pads yesterday. I was ready with longer high tensile strength M10 x 1.25 bolts and wider washers for the spacing. I noticed however that the original bolts had somewhat of an over hang through the strut, similar to the distance needed to space them. So I ended up using the originals. Just anecdotal more than anything. Also I did weigh the two discs. Baring in mind that the RS6 discs were cross drilled AND worn down (both will make lighter), and the phaetons are not cross drilled, the difference in weight was 1.5kg (RS6 6kg, Phaeton 7.5kg)

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