Well, today's rig is one of the biggest ... Did I mention there's no clutch? It's an 18-speed Eaton UltraShift, so all you have to do is hit the gears and just keep pumping that gas.

It's no surprise that engineers and designers are furiously trying to green long-haul tractor trailors. Just like airplanes, the profit margins are small, so ekeing out a 10% improvement in fuel ...