OK, so I guess my last idea of WTF could be wrong (that the fluid lines were swapped front/rear) appears gone.

-Some time around November the ebrake broke when engaging. later determined all cables snapped
-Truck seemed to operate all other brakes fine.
-Rear brake line broke. Let it sit and drove maybe 3 times over a period of about a month-6 weeks.
-Drove truck again one day and another line went (probably feed for front brakes from M/C) and lost all brakes. Got it towed
-Mechanic replaced all brake lines and the rear pads as they were getting low

Now the truck doesn't seem to stop well, but most importantly the rear brakes/rims get VERY hot to the touch. Could feel a drag on the truck at speed. At first i thought the ebrake drums could be dragging for some reason as even when no brakes engaged it wasn't easy to turn. I backed them all the way off. I replaced the rear PS caliper as with brakes not engaged and rear axle off the ground, the PS wheel would basically slow/stop rotating then 'break free' and repeat every 5 seconds.

Put everything back together and thought all was well. Drove it for an hour and when I parked I could smell the pads on the rear again. Rear rims hots to touch (I think both sides), front barely warm. On the way home I checked after driving on the highway and they seemed fine so it seems like it is more an issue when the brakes are applied than always dragging but not sure. I don't understand how it could be effecting both sides unless its further up. I can double check the lines are not pinched closed? The turn from vertical into the M/C isn't the best and there is a slight crimp there but don't think that's enough to make a big deal.

I don't drive the truck every day but i guess i need to do a couple shorter trips and see if it gets hot from just driving (i.e. a dragging issue) or if its only in stop and go? Open to any suggestions. Guess I can make sure the front lines are bled, didn't double check that...

I have a vibration on the highway now, so I assume I cooked the grease/diff lube and probably the bearings now too. Wonderful.

 

Hmm. I disassembled everything and it seemed OK, but i'm going to double check what is suggested here:
Diesel Place : Chevrolet and GMC Diesel Truck Forums - View Single Post - another soft brake thread