Caterpillar reported the Tier 4 Final 794 AC hauler successfully completed field validation, and exceeded requirements while hitting the same production metrics as the predecessor Tier 2 hauler. In tests, the Tier 4 hauler delivered lower operating costs by reducing diesel fuel consumption, Cat reported.

The 794 AC features the 3,500-horsepower Cat C175-16 diesel engine and has a 291-metric-ton (mt) (320-ton) payload capacity. The Tier 4 unit is equipped with an exhaust aftertreatment system using a selective catalytic reduction system, which uses diesel-exhaust fluid to reduce emissions of nitrogen oxides. The aftertreatment system is aligned with truck preventative maintenance intervals to maintain high availability, Caterpillar reported.

The same system is expected to gain European Union Stage V certification for the 794 AC.

The haulers were tested in a variety of applications, including in cold and hot temperatures, uphill hauls and flat hauls, Cat reported. In a copper mine, the Tier 4 Final haulers hit the same performance metrics as Tier 2 haulers, but logged a 5.6% less diesel-fuel burn over the haul cycle.

During field validation, the Tier 4 Final trucks accumulated 10,000 hours of operating time.