$25,000 to $65,000 if he works for a trucking company. If he is willing to truck cross-country and take calls at two am to take a run, the higher end, otherwise, the lower end. If he owns his rig, he can gross $200,000 - $250,000 a year and net only $50,000 to $80,000 of it... Trucks eat fuel like a bear, and a truck loan is as much as a mortgage for a house. By the time you pay that off... it's time to replace the truck. And if you own one, you're either in it, or under it. The upkeep is cheaper if you can figure it out for yourself.
But for some folk, it's the only life.