I rebuilt the system as it was due, fronts have been done for many months now (and working fine), then did the MC as it dragged in the past. Rears were like fronts, needed to be done. Dust boots torn, calipers grooved, etc.
I had a helper pump the brakes while it was on ramps (both axles) I could not see evidence of seepage/squirting anywhere. Also I had my pressure bleeder on there, nothing to be seen.
It's a Texas car (has been entire life) so the loss is odd. I traced the hard lines to the rear and they're sound. Same with the front. The only one I could not see easily was the passenger side.
I run PILES of the Cardone calipers, very few fail for me.
So if MC did leak into booster, would I need to pull booster to drain? Oil change too (I just changed it
)?