Weight transfer and traction has a lot mote to do with stopping than the design of the brake system. It's not uncommon for the front brakes on any vehicle to do 70% or more of the stopping, due to weight being transferred forward during a stop. Add to that the fact that truck brakes are designed to handle a fully loaded vehicle, and rear wheel lockup when unloaded is pretty much a given unless some finesse is applied while stopping. "Finesse" and "panic" don't always go together, but the final factor is always "traction".
Jerry
