Although Kohler and Sterling use several different types of rollers for their shower doors, the basic installation and replacement of all the rollers are the same. Proper installation is important as incorrect installation can cause the doors to slide poorly, make grinding noises, and/or even jump the track. However, ensuring that the rollers are correctly installed is quite simple to do.
When installing the rollers, the "nut side" of the roller will always be installed against the top frame flange or hanging bracket of the door.
The outside of the roller will always face the same way as the panel you are attaching it to. If you are installing rollers on the outside panel (the panel closest to you when standing outside the bath/ shower enclosure) the outside face of the rollers will be facing you when you are standing outside the unit.
Outside Panel: Outside face of roller faces out into the room
Inside Panel: Outside face of the roller faces into the shower/bath
If the rollers are installed correctly and the panels still do not slide easily, check to make sure there is no debris in the roller channels inside the top track of the shower door.