M1028 Front Brake troubles

It all started when my front LH caliper was sticking on my 84 M1028 that I just bought. I figured it needed some lube, so I took it apart and grease it up and put it all back together. Just so were on the same page Ive owned like 6 of these trucks, so this isn't my first time working on one. Any who, I put it all back together, tire back on, started the truck hit the brakes a few times, went to spin the wheel and it was locked up solid would not spin what so ever. Something to note is when reinstalling the wedge and spring it goes in pretty hard, I had the hammer it with some pretty good force to get it in.

I assumed at this point the caliper is bad. So I replaced both calipers and soft lines, gravity bleed the brakes, fresh fluid. Bleed them totally out. Now both sides are locked up solid. I went on to replace the MC and proportion valve, and hardware. I put it back together. rotor spins with slight drag until I start truck and hit the brakes. then both sides lock up solid. I tried driving the truck still no good. I even removed the bleeder from the calipers and still they are locked up. Which leads me to believe its something with the caliper not sliding properly.

Just came inside from working on it today here is where Im at. I took the passenger side apart, removed the little clip on the pad thinking maybe it was catching and when I went to reinstall the wedge and spring it went in VERY easy, two or three taps with the hammer. Tried the same with the drivers side. Rebleed the brakes. Drivers side is still locked pretty good. Passenger side is a lot looser than it was.( tire in air, give it a good spin and will spin half a turn before it stops.)

Im completely out of options here. Pads are almost brand new and flat, hubs spin nice and smooth, rotors arnt warped or anything of that nature.

Master cylinder not letting the fluid return?

Scott

You said you replaced the rubber flex hoses to both calipers ? The inner lining can come loose and act as a "one-way" check valve on old hoses.

if you have pulled the bleeder and the calipers still do not let loose, then there must be a problem with the slides on the caliper, if the caliper cannot slide, one side of the pad will stay pressed on the rotor

May help. May not. When I take the calipers off of Dana 60 axles or any calipers I use my 2" rolok grinder and polish the upper and lower bracket grooves on the hub/bracket and apply grease/never seize to the groove, wedge and spring. Clean it well like I am sure you have done and it should move freely. Also the wedge and spring are a very inexpensive part. It takes more time to clean them than it would to just replace them. A new bolt comes with that serviceable item set. Good Luck. Report back.