Problem with Craftsman Garage Door Opener Screw Drive
I have a 1/2 HP Craftsman screw drive garage door opener model 139.53991.
When it gets cold the garage door comes down half way, stops, and then goes back up.
If I release the door from the track and try the opener, the track rattles when the trolley gets to the center of the track.
This is the same spot where the garage door stops before going back up.
The manual says not to lubricate the screw/rail.
What is my problem and how do I fix it?