Ultra-Class Mining Haul Trucks

01

What is it?

Ultra-class haul trucks are rigid-frame vehicles generally defined by payload ratings of roughly 300 short tons or more. They carry blasted rock from a loading face to a crusher, stockpile, or waste dump, repeating the same routes around the clock.

They exist because moving material is one of a surface mine’s largest operating costs. A truck must combine extreme payload, braking and cooling capacity with predictable cycle times on steep, dusty haul roads.

Fun fact: the tires on the largest LMT are roughly 13 feet (4 meters) in diameter.

02

Typical applications

• Open-pit mining
• Overburden removal
• Ore transport
• Quarrying

03

How it works

A shovel or large excavator loads the body in several passes. The truck follows a dispatch assignment, climbs or descends the haul route, queues at its destination, tips the body, and returns empty.

Diesel-electric models use an engine-generator set to power wheel motors; mechanical-drive models transmit power through a gearbox and final drives. Operators—or an autonomous haulage system—coordinate speed, spacing, right of way, loading position, and dumping.

Fun fact: The Cat 797F carries a nominal 400-ton (US) payload. Caterpillar describes its six tires as roughly 13 feet (4 meters) in diameter. Source: Caterpillar’s 797F description.

At the Caterpillar Visitors Center in Peoria, Illinois, visitors can experience a virtual ride in the bed of a large Cat 797F display. The center’s current exhibit description does not describe it as an operational truck.

04

Why it matters

Truck availability and cycle time directly constrain mine throughput. Small changes in queuing, spotting, road condition, or payload consistency compound across a fleet of dozens or hundreds of machines.

Automation can remove people from collision, rollover, fatigue, dust, and vibration exposure, but it also makes communications, road design, fleet orchestration, and recovery procedures more important.