I've got some of those old Anderson sliding doors in my sunroom, probably circa 1973. The door that gets used most pulls harder and is obviously worn a lot more than the others. Can I buy replacement rollers and other hardware for these doors? If that's not possible, what kind of maintenance should I do on it?
A lot of time the problem is just accumulated gunk in the track and bearings. A real thorough cleaning and then lubrication with silcone of the track and bearings can work wonders. If the door still feels gritty then it may mean the rollers need replacement.