Hi Glyn, I only used brake fluid on the slave bore and piston seal as per manual. I did, however, put a fair bit in the cavity between the top of the piston and the seal that the push rod passes through. I did get a bit of air out when I was flushing the system so maybe my slave seal is actually on the way out (even though not dripping) and some of that grease got sucked into the system at some point? Keith |