IMO and past experience, mounting a bike rack to the rear bumper of a Jayco HTT is a bad idea. There have been recent discussions on this forum regarding this same question, so you ay want to do a little digging in older threads and find the discussions. Swagman makes a 2" receiver adapter which bolts to the 4" rear bumper of many RVs, and you attach your rack into the receiver, load your bikes on the rack, and voila; you're done!! The only problem is that Jayco bumpers--and probably most manufacturers' bumpers--aren't strong enough to withstand the swaying and bouncing that result from driving down the road. I installed one last year, mounted it according to the instructions, put 3 bikes on my 4-bike rack (one of which was a child's bike) and discovered at our destination that the steel bumper was tearing; the welds at the frame were fine, but the steel wasn't strong enough. The dealer where I purchased it (TT and receiver adapter) from replaced the damaged bumper, and it was on my dime that they installed 2 reinforcement brackets so it wouldn't happen again. The folks at Swagman told me that their product is specifically NOT for Jayco trailers, which would have been nice to know before hand. Before doing anything, I would talk with the service department at your dealer and tell them exactly what you are planning to do; they should be able to assist you so that you do not have problems. Happy Camping!!
2015 Jayco 32 TSBH
2015 Ford F-150 3.5 EcoBoost