You're well on your way to figuring out whats been plaguing you with these brakes. You know its holding pressure on the fronts, and it takes some force to spin them freely, right? One of three things are happening here. One, the slide pins that the caliper slides on are sticking or frozen(easily happen where you live in roadsalt paradise). Next, the caliper piston itself could be sticking in the bore of the caliper. Lastly, hydraulic, or brake fluid pressure could be holding, and not letting off when you let off the brake pedal, meaning its pushing against the calipers still. Using the right size wrench, open up the bleeder on the offending caliper, and see if fluid comes out, and if the wheel turns freely afterwards. If it does, then something is holding pressure on the brakes. If not, you have an issue in the caliper(s). If it is holding pressure, then you need to determine if its confined to the brake hose, or further upstream. Pump up the brakes, and get the calipers sticking again, and loosen the brake line on the master cylinder side of the brake hose. See if that gets you the same effect. If it doesnt, your hose is the, or a problem. If it isnt, then it will get more involved, but I am betting its either a hose problem, or caliper problem.