F150 and a Camplite 6.8

My rear axle weight is at 4800 pounds loaded. That's with a travel lite 800sbx on my 2010 f150 crew cab 6.5. The truck handles it great. I have approx. 10,000km with the weight over the 9.75. I also tow a boat with this setup on occasion. When I rotate the tires I check for bearing wear. F150 has had the 9.75 rear end in the trucks for quite awhile. I see contractors overload these trucks and run them hard daily. I haven't been able to find any 9.75 failures online. I feel the ratings are a bit of a game. Bearing part numbers are the same for the 9.75 and 9.75hd. Hell my buddy minivan has a payload of 1100 pounds.