The vehicle in question-1991 Jeep YJ, D60 and 14Bolt, Atlas, TF999, Wilwood calipers (D52) at all four corners, Wilwood adjustable proportional valve to the rear calipers, Dave's Custom Unlimited Master cylinder with dual diaphragm booster, all new hard lines with short steel braided lines at calipers. Only thing original from the Jeep is the pedal it's self.
I don't drive the Jeep very much, it's trailered most places but I've been dealing with this for a couple of years now. With D44 axles and now 1 tons.
Now, The brakes themselves work good, stops fine (even in low range crawling). The pedal feels good, never goes to floor.
The brakes and pedal work 100% correct when cold. As I drive the vehicle on road or off road the pedal starts to hang up or drag, brake lights start to stay on. The more I drive it the worse it gets, to the point I can feel the brakes themselves dragging. I have to lift up on the pedal with my foot to get the brakes to let off and the brake light to shut off.
I've tried replacing the brake booster (under warranty from Dave's) once, no change. I inspected the brake light switch, seems to be working correctly because this condition only happens when the vehicle is driven not after the Jeep sits overnight. I tried getting the brakes warmed up and the pedal to stick, disconnected vacuum hose but the pedal was still stuck?
This one has me stumped? Any help or suggestions would be appreciated.