Larry, this sounds like an adjustment. Most likely is window stop bracket has moved, or the lift mechanism is jamming just before it reaches the stop. You will need to remove the door trim panel to eyeball the mechanism to make the diagnosis. If you get a good up and down motion w/o crunching or noises, you are most likely in need of an adjustment of the mechanism. Check the capscrews that hold the regulator in the door. Good candidates for being loose.
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.