If you are a semi truck aficionado, chances are you have heard of Paccar. This colossus of the commercial trucking world is an unassuming giant for the uninitiated, but it quietly owns (or once owned) ...

Take a ride on any major highway around the world, and you're sure to see a familiar sight: armies of semi-trucks zipping by or trudging along, filled with all the things we buy at our favorite shops.

Have you ever wondered why some semi trucks have one set of wheels and others have two sets crammed together? That's because some semis use a single axle while others have tandem axles, but why is it ...