The Collaborative International Dictionary of English v.0.48:
Hauler \Haul"er\ (-[~e]r), n. 1. One who hauls. [1913 Webster] 2. A trucking company; a freight transporter using trucks. [PJC]WordNet (r) 3.0 (2006):
hauler n 1: a haulage contractor [syn: hauler, haulier]