[Motor31]

The first line of your post and the very last line are your answer. Your trailer is more than the truck is built to handle by the manufacturers own statements. Yup you probably can get away with it, for a while. There are lots of folks who do but eventually the consequences of ignoring the engineers figures will catch up to them either by equipment failure or worse. It's up to you as to how much you are willing to gamble. It's only your life, property and that of others on the road at stake vs your choice of a truck not up to the job. Kind of like russian roulette there are more chances to get away with it but that one incidence of losing the bet and the results of being held accountable can be a bit messy.