I purchased an 85 740 GLE which had a problem with the front driver side break. The previous owner said the break hung up and the wife drove it until it just would not go any further. Had towed home, sat for a year. I have replaced the brake caliper and rotor with one from an 87? 740, replaced both brake hoses on that side. I swapped the entire caliper unit, pads and rotor, cleaned and lubed the caliper guide pins and sleeves (upper and lower). Result, brake drags, and I assume that it is the same problem as original owner had. A hard couple of wacks with a rubber hammer on the caliper will release the unit. I believe the unit has the updated sleeve and bolt. I do not see andy crimps in the steel line to this caliper. I have checked the vent hole in the brake fluid container. I removed the cap to see if that would release brakes, no change. I even opened the bleed valves, no change. When I initially installed the caliper and new hoses, I replaced and bled the entire system. Any suggestions?