We have a 2011 AF 1140. Haven't had this problem however we have had two rollers come loose. It didn't happen at the same time. Fortunately the rollers ended up on the floor when they fell out. They could have fallen out of sight. Wasn't too hard to reinstall. Try putting the slide out about two-thirds and look up under the slide. you should be able to see the tracks and the rollers. They are about an inch in diameter and held in place with 1/4" nuts.
The point is, if one of the rollers fell off, that could be affecting the slides movement. Just a thought.