Haul trucks are off-highway, rigid dump trucks specifically engineered for use in high-production mining and heavy-duty construction environments.
Most haul trucks have a two-axle design, but two very well known models from the 1970s, the 350T Terex Titan and 235T Wabco 3200/B, had three axles. Haul truck capacities range from 40 short tons (36 t) to 496 short tons (450 t).
Large quarry-sized trucks range from 40 to 100 tons. A good example of this is the Caterpillar 775 (rated at 70 short tons (64 t)).Quarry operations are typically smaller than, say, a gold/copper mine, and require smaller trucks.
The largest, highest-payload-capacity haul trucks are referred to as ultra class trucks. The ultra class includes all haul trucks with a payload capacity of 300 short tons (272 t) or greater. As of October 2013[update], the BelAZ 75710 has the highest payload capacity, 450 metric tons.