My dealer said if we went over the rating on the bumper it would void the warranty or something to that effect.
Having said that, I had a friend, a certified welder, beef up all the welds to the frame and bumper and also added flat steel and angle for reinforcement. We then added a receiver hitch for the bike carrier. It's about 40 lbs and carries two bikes at around 25 lbs. each. No Worries.
Apparently it was a bit of overkill. He was telling me how much weight one weld can be rated at. Don't remember the number but it was quite a bit.
Bikes rode for almost 7000 miles on last trip and didn't move an inch per my wife who was following behind.
Dwayne and Susan
Jiro and Phoebe-4 legged family members
Mike and Dana - Traveling buddies
2016 Ford F350 XLT 6.7 Powerstroke DRW 4X4
2016 Brookstone 395RL