I have a 1994 FJZ80 that only loses pressure on the front passenger brake. According to the mechanic that has done work on the vehicle he has replace the brake lines, calipers, pads, master cylinder, booster, and the load sensing proportioning valve. He found the pressure loss after conducting a rear pressure test and then a front pressure test. I sent him the vehicle because the brake was almost going to the floor if I needed to stop. There was pressure on the brake when the vehicle wasn't operating. All of this information is to the best of my knowledge and the mechanic passed away recently so it will be hard to get more answers from him. Has anyone had this issue?