Heavy hauler
![Two MAN SE ballast tractors pulling and one Mercedes pushing a 100,000 kg (220,000 lb) transformer on 10-axle lowboy trailer](/Images/godic/202501/17/Rawcliffe_Ballasted_Outfit1620.JPG")
![ALMA antenna in transit on a self-propelled modular transporter](/Images/godic/202501/17/Alma_antenna_in_transit1620.jpg")
A heavy hauler is a very large transporter for moving oversize loads too large for road travel without an escort and special permit.
A heavy hauler typically consists of a heavy tractor unit unit and multi-axled lowboy flatbed trailer. Some trailers may have independently steerable wheels, and several might be towed by one or more tractor units in a train.