[Jdub]

Good that you got into the door. Has anything happened or changed to your door? Did this behavior happen over time or suddenly?

If you have not already, clean all the channels, etc. of old grease and inspect everything. Be very observant of things you find in the bottom of the door and lay them out on a workbench for inspection.

Carefully roll the window up and down and observe how the window moves (tracks) downward from the inside. Any click in the X frame? Use WD-40 as the window binds up and see if shooting it into areas eases the movement. Otherwise, I'd suspect you find something in the bottom if it were entirely mechanical and not a solid re-greasing job.

Good luck! Cleaning and regrease of the roll up windows is a revelation after X number of years.