I've got a good friend with his Masters degree who quit teaching school to drive a truck because it paid so much more. He makes a great deal more than $41 K a year. It must depend on the particular company and the alternatives where you live.
* Licensure (e.g. if you have a Hazmat endorsement) * Route type (Long haul pays a lot more) * Driver's safety record * Employment status - Independent contractors who own their own rig vs captive employees Etc.