I use to run the 18K in a 6 foot bed Dodge diesel then I found out the guy that sold me my TH and superglide was off on the weight of my rig it weighs 22K not 16K. In mine the whole gliding operation is articulated to a BALL(not plain) bearing if it blows which mine did the TH will drop to your bed rails move rear stop by chains or the tail gate, my case tailgate was the only that keep me from loosing it completely and hitting someone behind me. I think they updated to a higher rated bearing you might want to look at yours, 2007 time frame. After that I immediated sold it and the truck and went to the F-450 8’ bed. Ol 2500 dodge mega cab was rated @ 13,5K pulled 22K for good year and only blew two tranny flex plates, one SG bearing.
When this same dealer took off to show me how the SG worked the first turn out of the driveway he hit my rear window area and ended up paying for the body damage. Guy had 30 years in RV sales and repair. Part of my learning experience to never listen to sales people regardless of their experience level.
All I can say is be careful with your turns, you have to clean and re marine grease the rails after each use, check update and carry an xtra bearing inspect it occasionally. O and get some air bags or shocks or something for squat.