Our Elkridge 5r has the rear bumper with attached spare tire that pulls out to accommodate additional storage. This is secured to the frame with clevis pins in either the extended or non-extended position. On my last trip when I returned home I found the clevis pin on the right hand side missing. Fortunately the left side was sufficient to not lose the bumper during travel. I have always positioned the clevis pin so that the hairpin clip closed-end rotates up which would minimize the chance of the clip becoming dislodged and the clevis vibrating out. I suspect that someone removed the hairpin and clevis while I was at my campsite, but the possibility does exist that it happened during travel. Just wanted to call this to others attention that have this feature. I will be replacing the clevis pins with grade 8 bolts and lock nuts as I almost exclusively travel with the bumper extended.
DSCF0284 by camelwhit, on Flickr
DSCF0284 by camelwhit, on Flickr