Hello I have a 2001 tahoe my drive side window when it goes down it makes a loud grinding noise when it gets to the bottom I have to hit the up to stop it then then just yesterday when I go to roll it up it stoped and made the same noise I had to pull it up by hand any suggestions on what it might be

 

Welcome to the forum.
You are probably going to need to remove the door panel in order to diagnose what's going on. Best guess is that the gear is stripping on the motor.