Hello. I would appreciate it if anyone had any suggestions for my current issue. The car is a 2007 G35, Coupe, MT.

In 2012, after a long time without driving the car (8 months, military deployment, dead battery+girlfriend, long story) the rear passenger brake began to stick. I didn't realize this was happening until the pad was pretty much gone and the metal of the bracket was scraping the rotor. I ordered a rebuilt caliper, replaced both rear rotors and put on new pads.Not being a car expert I bled the brakes with the assistance of the mechanic at the on base auto hobby shop.

Fast forward to 2 weeks ago, I noticed a slight noise from the same brake while the window was rolled down. Popped off the rim and sure enough, the pads were almost gone. Fortunately, I caught it before there was any rotor damage. Based on this, and the sound I heard it seems like the caliper was dragging when the brake was released, not fully clamped down. I assumed the caliper seized, so I took it off. I removed the piston and the surfaces were smooth with no sign of scratches or corrosion I'm assuming you would see with a truly seized piston. The sliding pins seem OK as well.

In addition to the fact everything is coming up clean in the caliper. I would be amazed to happen to have 2 bad calipers in the same position. The other brakes all seem fine, which leads me to believe the master cylinder isn't to blame...

The only thing left is the lines leading to that particular piston. Am I missing something? Is there another component that could be causing these symptoms?

If it is the line, do I need to replace one rubber line, all rubber lines or the complete line leading to this brake? Is there a way to check?

I'm stationed in Germany, so getting parts takes a long time and being without my car has been a hassle. Also, the car is immobilized in my driveway, so bringing it to a mechanic will require a tow and be a major pain...

Any advice would be welcome. Thanks!!!