HP 2840 printer paper jam

Question

My HP2840 jams ever time I try to use tray 2 (loading paper from the bottom tray). It works fine from tray 1, the front tray. I've replaced the separation pad in the drawer and the pick up roller for it that is underneath the unit. I can't figure out why it jams ever time. The paper path seems to be clear. What's the deal???