Review: Hitachi AH400 ADT

By: Ron Horner

Date: 05.08.2020

Living up to Hitachi’s reputation for building tough, heavy machinery is the AH400 articulated dump truck—a model now designated the Bell B40

Reviewer Ron Horner with the Hitachi AH400 articulated dump truck

I was fortunate to be able to gain access to a construction site in Darra, near Brisbane, to monitor the progress of the works taking place and to evaluate some of the equipment, including a 2007 40-tonne Hitachi AH400 articulated dump truck (ADT).

The Hitachi AH400 truck at work at the PGH/Boral clay mine site in Darra, Queensland

The 2007 model Hitachi AH400 is in a very good general condition considering it has clocked up 7000 hours of mine-related work. This AH400 6x6 ADT has fully integrated fire suppression system fitted, a ROPS/FOPS cabin as standard, aircon, two-way radio, AM/FM radio, multiple E-stops located in easy-to-reach areas such as the cabin and around the machine, fully automated tail-gate, and safety handrails.

It runs a DaimlerChrysler OM 501 LA 12-litre turbo diesel engine delivering a gross 422hp (315kW) and an Allison HD 4560R auto transmission with an integral retarder. Among the innovations introduced into the Hitachi ADT range are a pitch-and-roll sensor, which stops the body being operated if the truck is in an unsafe position, and an operator- or site-selectable maximum speed control, which automatically deaccelerates the vehicle and applies the retarder to prevent onsite speeding.

In the cabin

The cabin of the AH400 is as comfortable as one could wish. The machine has excellent operator comfort with a good seating arrangement and good viewing to the front and sides. A reversing camera monitor is located to the upper right, and E stops, gear shifter, brake, and gauges are all in easy range.

There’s a passenger seat complete with belts for a passenger should the situation arise. The cabin noise is minimal, and one could easily hear the radio and two-way when under heavy load.

On the job

Parade of nations: Hitachi, Cat, and Heking working together

The Hitachi AH400 handled everything that could be thrown at it on this project. The in-dam conditions were horrendous as oozing, sloppy mud was hauled some 800 metres (round trip) up steep inclines and down through unstable, wet gullies.

The AH400 had to deal with oozing, sloppy mud, steep inclines and unstable, wet gullies

The automatic tailgates were invaluable, as they minimised the spilling of wet materials and, therefore, saved on continual maintenance and upkeep of the haul roads. Gear shifting was a smooth operation with the Allison transmission handling the heavy going with ease.

That transmission has some advanced and sophisticated features that allow it to select the optimum shift points based on the load and driving conditions. Power is automatically distributed equally to all three axles by limited-slip differentials that provide constant traction in slippery conditions.

The AH400 has an exclusive on-board weighing option that presents the operator with real-time information on the payload while the machine is being loaded. A limp-home mode can be activated if the machine is significantly overloaded, and there were many times that this occurred when I was in the cabin.

When it comes to steep slopes, the parking brake is automatically applied (even if you fail to apply brakes manually). This ensures the truck can park in position and avoid coasting away. Hitachi Construction Machinery is up there as a world leader in all classes of heavy machinery manufacturing and design, and its range of ADTs is definitely no exception.