Wow that first vehicle was amazing, I'd have loved the heck out of operating that baby. At approx. 9:00 mins. They show a split frame dump trailer. I don't see what's so fancy about that one. Here in the Buffalo, NY area I drove one of those model's pulled by my Mack Superliner back in the mid 80's. That second model, looks like it would take alot of maintenance to keep the body clean from buildup, not practical for all soils. Tracked dumper is only slightly more useful than a screen door on a submarine. An off-road haul truck could have moved more in 1/4th the time.