Bob, having the trailer help you break is a good idea. I finished restoring a 1972 - 31' Landyacht that hits the scale at 7,200 lbs. I had everything working except for the breaks ( ran out of time ) . I took a two week trip thru Big Bend National Park here in Texas. As you may have heard all things in Texas are big and so are the hills. While decending down a very steep hill the brakes on my 2002 4x4 F-150 started to fade. My truck is equiped with the optioal towing package and 4 wheel disk brakes, but it's not enough when you have 7,200 lbs Airstream pushing you down a hill. Needless to say I'm in the process of working on the brakes before my next trip.
Best of luck,