So I'm next to positive someone reassembled the brake hose incorrectly before. It was twisted, and the connector (I'm almost certain) was backwards. I reassembled the hose the way I removed it (backwards). Now I realize the shouldered portion of the connector should be on the outside. I'll be replacing the washers and reattaching it correctly tomorrow when I do the driver's side drive axle brakes.
On a side note, I drove the MH 4 hours (stopping regularly and inspecting the brakes, brake lines and axle, re-torquing the lugs at 20 and 100 miles) and braking is already much better. Driving also seems smoother... like maybe greasing the axle helped remove some vibration. Eager to finish the brakes and see the total improvement.