I have just had one fitted to my cab.
Went from a 20 mm rarb ( on the S4) to a 22 mm.
Now it appears that after ordering the bar from a B7 RS4 cab, when I measured it and then measured what I had on my car it was no different and still only 20 mm.
So basically, what I found out at the dealers was that the B7 RS4 cab has a 20 mm rarb and if you want to upgrade to the 22 mm rarb you have to order the bar from the B7 RS4 saloon.
As already said but to confirm the rarb you require ( if you want 22mm ) is from a B7 RS4 Saloon, not from a B7 RS4 cab and is 8E0511409AL
I also ordered 8A0511439 clip and 8E0511327A mounting bush but was told by the indie who was due to carry out the work that these would not fit. Now, these may well fit but on their Etka system it gave a diff number and they didnt try to see if it would fit.
So they ordered the parts they thought they needed and I didnt see what numbers they were but I still have the mounting bushes 8E0511327A and clips 8A0511439 that they didnt use, still in the Audi bags if someone wants them. Send pm pls.
Have just re read the thread and the OP duffy has asked if 8E0511409AJ would fit, well that is the part I originally ordered but when I picked it up from my local Audi centre it was only 20mm and therefore no different to the one already fitted to my S4 cab and so I took it back to find a 22 mm one. As I said above if you want a 22 mm rarb you need part number 8E0511409AL Stabilizer Bar.
Hope this helps and good luck
