Drove to work friday am (20miles) pulled in and felt like there was a flat - after looking around the driver side rear wheel was hot and smoking - so i assumed a new caliper would fix the problem and replaced it. On the way home all 4 brakes started dragging. Also noticed that the brake pedal was hard and at the top. I cant believe that all of the brake hoses are bad at the same time so i am looking for advice, i read on another forum that a power steering fluid flush helped with pedal problems - any other thoughts on what to try next? On saturday i drove to the fuel station and back (3miles) no lagging, only thing is the pedal is still at the top so i have a feeling that the longet the truck runs the more chance the brakes will lock up. Seems like it may be tied to the booster overbuilding pressure behind the master cylinder? any thoughts? how do i test that?