Fixing a Sliding Glass Door:

           I have been fighting with my  sliding door on the rear of my house for awhile now . I tried cleaning where it slides but that only helped a little.I tried putting soap on the rail just like your old sled rails. Did not help at all.  

           So I turned to the trusty Internet to help me find a solution.Apparently there are wheels on the bottom that only last about 3 to 5 years. My door is 8 years old so I guess I lucked out.

           First thing to do is take the door out of casement. On the bottom of the door there will be a small hole on either end. (have someone help you and hold door, these doors are very heavy) stick a screwdriver in there and turn counterclockwise. This will raise the wheels up and lower the door. On my door ,I had to also slide the rail out because the door would not clear the top casement.Now the door will clear top casement, pull towards you and lay it on its side.

Now you can access the wheel Assembly's.On mine there is only one screw holding the wheels in . Unscrew it and pull the wheels off. Mine were completely broken .The wheels were broken right down the center.

There was no markings on the door ,so I didn't know the manufacturer which would of helped a lot. So off to Home Depot with part in hand. No luck There so off to Lowe's. They had something really close so I took a chance and it worked out fine.

I had to tap these in as they were a little wider than the original. I lined up the screw hole an screwed it in.I gave both wheels a nice shot of wd40 and I;m ready to install door into casing. Buy before you do that , clean all the gunk out of where door slides.
Put the door back in, turn screws clockwise to raise door up, now slide rail back in, adjust screws again and your finished. Door should move with one finger.
You just saved yourself about a $100 to $200 by doing it yourself.
Oh ,and one more thing, Make sure you tell the rest of the family you fixed it because if they pull as hard as they usually do, they will probably put the door right through the wall.