my passenger's side window has always worked flawlessly, the drivers side has always been a little slow to go up and tiled forward, and more recently it will stop dead half way up unless I grab it and tilt it back.
I widened and lubricated the front track and it only improved it ever so slightly but nothing worth a damn.
I noticed the same thing as above... I think it has nothing to do with the front and rear rubber tracks and everything to do with the center guide...
I can push DOWN on the top of the window near the back and the window will roll up flawless every time... as long as you can prevent it from tilting you can have a window that goes up and down properly.
easing the pressure on the front track only treats the symptom... the cause is the fact that window is allowed to tilt at all.
looking at my well working passenger's side window the guides are snug against the center track... on my drivers side the front guide is warn down a fair amount.
the window motor puts more pressure up on the back than it does in the front which will naturally make the window want to tilt forward, the center track is what keeps it from tilting, the front and rear rubber guides are just to protect and seal the window away from the metal in the door... when the center guide isn't working they exacerbate the problem but I don't think they're the root cause.
I'm going to try the zip tie method sometime this week and see if it works.