Describe 2 piece seal. I think it is just a 1984 dually front grease seal. Nothing special that I am aware of. I only ever had 1 dually CUCV and I bought standard parts for it at Autozone, NAPA, or Mom and Pop auto parts. Same as civilian. I bought National seals. I hope that helps. Get the spindle seals and the dust seals that are in behind the spindle. Make sure you clean and grease the often neglected spindle bearings. Good Luck.