there's a somewhat popular secondary theory that the original Optimus Prime toy's alternate mode was actually inspired by the Kenworth K100, another semi-truck with the flat-faced cab-over-engine ...

It looks like Optimus Prime could have some ten-wheeled ... Based on a 2014 Freightliner Argosy cab-over semi truck, it's not exactly clear which character this is, but if the movie was to rehash ...

While Optimus Prime opens the film in the form of a rusted out 1973 Marmon cab-over truck, the autobot leader eventually takes the form of an awesome 2015 Western Star 5700-based semi. We'll see ...