window regulator question

[D-Rat]

my driver door is developing a 'catch' on the windo regulator...almost like a flat spot or something on the rotating assembly making the window go up hard every time the crank passes that spot each revolution.

Is this an easy fix or are my entire regulators shot? I haven't had the door apart, but remember a nylon rotating wheel that rolled inside the regulator track on an old Ford car I used to have...the wheel went to crap and it cost about $2 to fix....hoping it's that simple here.