I used to built American trucks a lot, I really liked them, but I stopped, started to built cars and European trucks. Then I found Brickonwheels on this site, I like his trucks and used them as inspiration for mine.
My peterbilt is a lowered show model, I designed it myself, it doesn't really exist. The 2 axels in the back are connected with the engine and with a thing on the roof you can steer. The front doors open, the door in the sleeper doesn't, the hood opens and underneath there's the engine with rotating fan (driven by the backwheels). There are 97 extra lights on the truck, that brings the total on 107 (I think). In the sleeper are a launchcouch, 2 flatsceen tv's, a PS3 and a big soundsystem.