http://www.opgi.com/common/C980156LH-lrg.jpg
This one ^
At the top there's that little roller, well mine would stop spinning and the pawl that rides on it would grind on it, it would make a quiet scraping sound and pop if it finally broke free and spun. It started creaking and that's when I had enough lol. It really kills the ability to name it a nice car if it makes noises like that. I got a jack with a wood block to hold the door up, and loosened both and removed the top one, cleaned oiled and reinstalled.
I had to do the left rear door when I got the car since it started doing the same thing. I'm sure eventually the right two will do it and I will clean/oil them too.
Also I did more stuff to my car today (third time) Gave it a good wash/rain-x by hand for the first time this year, and then clouds appeared in the sky all of a sudden (unpredicted) and sprinkled for a few minutes... Just to make me mad. Oh well it's still clean gladly.