To determine if support brackets are needed to accommodate the weight of the bikes/rack you'd be placing in the Curt RV Bumper 2" Trailer Hitch Receiver # E-100 you would need to contact Keystone and ask what the weight capacity of the rear bumper is. You could also reach out to a local fabrication/welding company and have them take a look/weld on some extra supports to ensure that the bumper can handle the weight. view full answer...
While I am unable to look up the exact parts on your 2016 Keystone Passport GT 2670BH based on the weights listed for your camper it appears you have tandem 3,500lb axles. The 3,500lb axle would use the Bearing Kit # TMK52VR you found. As I cannot verify this is exactly what you need you would want to disassemble one of the hubs and identify the bearings used for your hub. It should be an Inner Bearing # L68149 and Outer Bearing # L44649. I also may be able to verify the bearings if you... view full answer...