Originally Posted by 40 to 332

Understood. I've always used Motul RBF600 and I agree that it does gradually darken over time … but I've never seen anything like this. The colour is a dark grey with a very slight greenish hue. After leaving the fluid overnight, whatever's in it has remained fully suspended. There is no residue or any particles at the bottom of the container, which I think typically occurs if the CSC or CMC fails. The fluid is very smooth and slick on touch. There is no evidence of any grit whatsoever. Very strange! I'll try bleeding the system again in a couple of days.