Well 90% of the time the brakes seem find on my 86 F150, but on occasion I will be coming to a stop and they will go to the floor. Usually I can recover by pumping them, but it sure does make me pucker up in all the wrong places. From what Ive read on here it sounds like the brakes might need to be bled. Is this true, or what else could this be? Brake fluid level is fine, but does seem kinda dirty. THANKS!!

 

Replace your master cylinder.