After I got my truck back from the dealer I searched another forum for problems with rear brakes and found an entire thread listing problems similar to mine. Most were either newer trucks like mine or older Super Duty's that had calipers replaced several times over the lifespan of the truck.
All reported rust/corrosion on either the piston or slide pins which caused the piston to not fully release or the pins which caused the caliper to center over the rotor. Both obviously produced drag on the truck.
What I find interesting is that for as many folks over there that had issues, nobody here did. May be because I was initially convinced that the problem was with the e-brake although the problem seemed to cease when I did not use the parking brake.
All reported rust/corrosion on either the piston or slide pins which caused the piston to not fully release or the pins which caused the caliper to center over the rotor. Both obviously produced drag on the truck.
What I find interesting is that for as many folks over there that had issues, nobody here did. May be because I was initially convinced that the problem was with the e-brake although the problem seemed to cease when I did not use the parking brake.