Has anyone replaced your Coleman/Fleetwood Thrust Nut Bearing? There are 3 types of bearings depending on the year. Here is a picture of a new one at coleman popup parts Here is a picture of a new one installed at the back of the camper in the bumper area from a satisfied customer of coleman popup parts My lift system chain feels like it has slack in it and as I crank down the roof, it jerks a little on the way down. I'm wondering if its time to replace this bearing. I found some other posts that said it's hard to remove the shear pin item #15 on page 7 of this parts manual by coleman popup parts. Maybe I should let my dealer do this. Thoughts?