Dodge Repair: Brake problem, dodge grand caravan, disc brake pads

Question
Hi,  I have a Dodge Grand Caravan 3.3 ('96).  The car was driving fine until one day after about an hour in to the journy there was loads of smoke coming from the front left brake caliper.  After looking, the heat generated was hot enough to melt my trim!  I took it to a mechanic and he repaired the problem(he replaced the caliper with a genuine part, disc, brake pads and any other bit damaged by the heat).  It seemed ok but 3 months on, the same thing has happend again but luckily I stopped before too much damage occured.  After checking it out, the caliper doesn't seem to rollback after you take your foot off the brake pedal,  Its not completly jammed shut but it takes some effort to rotate it.  I compared this with the other side of the car and that one seems ok,as soon as you take your foot of the pedal you can rotate it with ease.  I can make the piston retract only if i open the bleed valve first.  Every thing else looks ok, its all greased up and the sliders are ok too.

Thanks for you help

Jon

Answer
U could be looking at a Proportioning valve  or the master cly   but I doubt the master cly would only lock up one.
When u replace that part  also replace the rubber line on that side  if not done so already.
If u live near Atlanta I can look at this for u