New owner of 2003 RS6 C5 Saloon

[norwichphoto]

-replacement first aid kit arrived today (for completion)
-replacement headlamp switch arrived (original was scratched)
-fuel filter arrived also.
-big box of parts ready to collect at Audi as well.

[norwichphoto]

Tyres fitted and balanced. Two wouldn't balance nicely so on lookout for 2 19" alloys, althuogh having checked on my own balancer, they seem to be relatively true. They can go on the back until I find some better ones.

Brakes bled with pressure bleeder with new brake fluid ATE type 200 (formerly Racing Blue) DOT4 fluid but higher boiling points than regular DOT4

Cabin filter changed and the underside of the wiper linkage, master cylinder, header tank, pollen filter, hidden valley vacuumed out and blown out. Amazing how much crud gets in there.

Tomorrows jobs will be to torque up the front and rear brake callipers, to remove both front struts and to fit the new front springs. Aim is to get the car back on its wheels again, ready for the cam belt change. If there is time I'd like to start an in-situ tidying up of rear wishbones, and possibly fit fuel filter. Its quite satisfying being able to tick things off the job list...

[Human Joist]

Good effort mate. Remember we love the pictures on here. Think one of the rules is pictures or it didn’t happen

Something I will do when I fight off my roof liner to re do it

[norwichphoto]

Best laid plans of mice and men...

Car is back on its wheels at the back, but the front is still up in the air on axle stands. The upper control arms pinch bolts were seized and took ages to persuade to come out, and on top of that once the damper with the broken spring was removed, the spring was obviously very different. The old spring is substantially thicker than its replacement, and fewer coils to boot. Going to check with Audi...

Gallery of work in progress here Andrew's RS6 project

Attached is a photo of the original spring at the bottom, more coils and thicker wire, and the replacement on top. I’ve checked the parts system and
8E0 411 105 CK (3 green stripes and one violet) supersedes to 8e0 411 105 EK which is what's been supplied.

[IchBautAuto]

None of those look right to me. Here are my spring colour codes, Standard DRC springs on Bilstein. This is a sedan so the rear code may differ.

[norwichphoto]

The parts catalogue at 7zap is a little confusing, at least to me. It suggests four five options partially depending on weight code?

8E0 411 105 CH coil spring [supersedes to 8E0 411 105 EH]
- 1 blue, 1 white, 2 green
0JK code (weight category 10)

8E0 411 105 CJ coil spring [supersedes to 8E0 411 105 EJ]
- 1 green, 2 violet
0JL code (weight category 11)

8E0 411 105 CK coil spring [supersedes to 8E0 411 105 EK]
- 3 green, 1 violet
0JM code (up to May 2003) (weight category 12)
OJM code + 8Z5 (from May 2003) - 8Z5 = Not Hot Country

8E0 411 105 CL coil spring [supersedes to 8E0 411 105 EL]
- 1 yellow, 1 blue, 1 orange
OJM code + 8Z9 (from May 2003) - 8Z9 = Super Hot Country

4B3 411 105 J coil spring [discontinued without replacement]
- 1 red
0JM code + 2ME (I believe this is Sports Suspension Plus)


On my service book is the 0JM code.

[IchBautAuto]

I don't see any of those options matching mine. I'd say that there are a number of other options that aren't shown on 7 zap. I'm in the middle of some major floods at the moment so can't help you much more than that. My initial view is that the replacement spring is not a direct replacement. The spring characteristics will be all different.

Just to add, my suspension code was 2MC, sports suspension with variable shock absorption.

[Shoppinit]

There was a thread where we got to the bottom of the spring colour codes a couple of months ago.

[norwichphoto]

I've added to the colour code list. Australia would be classed as a hot country and those got different springs.

[norwichphoto]

Rear Springs:

4B0 511 115 DP
1 orange
OYQ (weight range 15)
OYR + 2MC (weight range 16) + Sports suspension
Discontinued, possibly replacement but info not given

4B0 511 115 DQ
1 orange, 1 grey
OYS + 2MC (weight range 17) + Sports suspension

4BO 511 115 DR
1 orange, 2 grey
OYT + 2MC (weight range 18) + Sports suspension

4B3 511 115R (Discontinued without replacement)
2 red
Saloon 0YR + 2ME (weight range 16 + Super sports suspension)

4B3 511 115 S (Discontinued without replacement)
3 red
Avant 0YS + 2ME (weight range 17 + Super sports suspension)

[norwichphoto]

I think I will dismantle the other side, get the non-broken spring and dig out my coil spring testing machine and try and work out spring rates for this and the other one.

[norwichphoto]

Using online spring rate calculators and using data I've measured myself where known, and making the same assumptions for data I don't have figures for, I think the standard spring for my car is approx 74N/mm and the proposed replacements from is about 62N/mm.

I've found two Sachs springs which seem to be much closer in specification to the originals, or at least the published dimensions are, so I've ordered a pair of each and we'll see what turns up in a few days.

I'm keeping notes on all the things I'm doing, and will post further info on this matter shortly, but I don't want to post information that in years to come could be taken out of context and someone falls foul of something because they didn't read the whole thread or someone had cut and pasted information that hadn't been proven.

[IchBautAuto]

You might also keep in mind eibach. I used their springs on my RS4 and very good. If they make a set for the C5 S6, they should work well. You'll find that most companies shy away from specific items for the RS6 as no one makes a DRC so they aren't a direct replacement.

[norwichphoto]

Eibach did list a replacement but 15.5mm wire diameter rather than 16.9mm.

[norwichphoto]

Have done some more calcs with the assistance of my brother and his 3D CAD software. Conclusion is that I'm probably worrying unneccessarily and the Audi springs are actually OK. By having thinner wire and less coils, the spring material is shorter by approx 80cm and if uncoiled to form a straight torsion bar would require similar effort to twist. By his calcs, original 88N/mm (502lb/in) and replacements 85N/mm (485lb/in)