I have to replace the master cylinder, so I thought this was a good time to change to dot 5. I have repainted my brake booster 3 times now and it's getting old. I read Bob Tiley's post that he just bleed the 5 through without flushing out the system. I don't want to or have the time right now to take the whole system apart. I have original brakes (front disc) and all new lines, but all filled with dot 3. I wish I had done this when I put all the lines in. Any thoughts on how this will work. Bob, how much fluid did it take to flush the whole system? I have a vacuum pump, what did you use? thanks for any advice.