I am try to build a 5 axle tractor(twin steer,tri-drive) to pull a heavy haul trailer(jeep 2axle, trailer 3axle, booster 2axle). Overall truck/trailer length 120 feet. I am trying to determine balance points to equally distribute the weights on all axles. I do know that the front steer axle will not carry equal weight. It will probably be less than the others. A CAD program that would allow me to test the different positions with different weight factors unladen and laden would help. I do not know which thread to post to to ask for help.