Cover story: Gaddum Construction Terex Trucks

By: Cameron Officer, Photography by: Cameron Officer

Terex Trucks’ iconic ADT engineering ensures operators like Gaddum Construction remain safe, comfortable, and productive in even the steepest backcountry

Peering over the side of the steep ridge, Guy Gaddum’s forestry road construction team is currently working on in the Omaio Forest, about 50km east of Opotiki, I’m genuinely surprised at the steepness of the terrain.

The hillsides—nearly all shorn of trees now, with just the last few months’ worth of work remaining—are sheer; the gullies descending into darkness as soaking rain sweeps across the yellow mud of the razorback road we’re standing on.


That the Gaddum Construction crew is operating Terex Trucks TA300 articulated dump trucks (ADTs) up here is impressive. But then, agility, power, and safety features all combine to make them a sure-footed tool for such country.

"Geez, this must be the steepest terrain you’ve ever operated an ADT in, then?" I ask driver Mikey Shaw as we stand on the leeward side of his Terex Trucks, as much out of the driving rain as possible.

Mikey pauses for a second and then, as nonchalantly as if I’d asked him what’s in his lunchbox today, he replies with, "Nah, over the other side is a fair bit steeper than this."

Ah. Okay then.

ADTs at work


There’s still little room for error here. The Gaddum Construction team has two Terex Trucks TA300s working the hill country (on a good day you can see White Island steaming away out in the Bay). The Terex Trucks, sourced through New Zealand distributor, Porter Equipment, are hauling end material and metal for road-building. But with the precarious logistics of this job in mind, Guy Gaddum purchased them for their log-carting abilities, too.

"The Terex Trucks replace a couple of other dumpers we’ve been using for a long time," he says. "I knew we would be doing a lot of log hauling, as this block comes into the final stages of its harvest, so it seemed like the right time to upgrade the machinery.

"Those older machines were sourced through Porters as well and they’ve more than paid for themselves over time. But these new trucks really step things up in terms of technology and driver comfort."

Case-in-point: Guy says Mikey came on-board with the company as a general labourer, but after driving the Terex Trucks TA300 for a couple of days, he can’t get Mikey out of the thing. It’s the comfiest place to be, especially on cold winter days.

It’s the backend of the truck that remains most important to Guy in terms of the work schedule. The basic dimensions of the TA300’s tub—17.5m³ heaped material capacity—obviously come in handy. But it’s the extra tech that reduces all-important cycle times, ensuring the team can work efficiently regardless of the terrain or weather.

"Having on-board scales really helps the driver utilise the truck at its capacity, without any compromise to safety or machine performance. And for the digger operator, Terex Trucks’ light system is great, too," Guy says.

The light system, featuring bright LEDs mounted to the rear of the Terex Trucks’ cab, lets the excavator driver know when the material being loaded is within the maximum 28-tonne payload range (for the Terex Trucks TA300), eliminating guesswork.

Guy says he’s also impressed with the big machines’ power and braking abilities in the wet as well, although so far, only as an observer.

"Over the years, dump trucks have gone from the simplest machines in the shed to some of the most technologically advanced. I’m not even inducted to drive these things.

"Porter Equipment runs an awesome induction programme as part of the handover process, and it’s really beneficial for our guys to get the most out of the trucks from day one.

"There used to be a time many years ago where you might get a machine delivered and you’d be on your own; not so these days though. We have a great relationship with Craig and Matt from Porter Equipment and they’ve got our back should we need it."

The Terex Trucks reputation


Terex Trucks has built a solid reputation over nine generations of machine, providing contractors like Gaddum Construction with dependable mobile plant, capable of working the hard yards. With operator fatigue such a consideration for companies on the modern worksite, Guy says he has noticed first-hand how Terex Trucks’ heavy-duty suspension and cab set-up helps mitigate this.

"I saw straightaway how the adjustable air seats and the underpinnings of the Terex Trucks’ help keep the operator centred and level over rough ground. When you compare that to the older machines, which drop and bounce and move the driver around much more severely, you can see that a day spent behind the wheel of each machine would result in different levels of tiredness.

"Also, with a machine that’s pitching and rolling as it progresses up the haul road, the driver is going to take things much more slowly than they really need to. The Terex Trucks’ smoothness means the whole load and off-load process happens a lot quicker."

While the steep terrain at Omaio demands plenty of power (370hp and 1880Nm maximum torque in the TA300), Terex Trucks’ auto-retard braking system is just as vital. In these 10th-generation trucks, this has been simplified to be fully automatic; the operator merely needs to lift a foot off the pedal and the retarder comes straight on, equating to a lot more control in a steep descent. The system is adjustable through six different stages, so the driver can choose from very soft to very responsive.

Despite the mud, Mikey says that he’s in 4x4 mode most of the time, but the Terex Trucks’ drive system detects exaggerated slippage in microseconds, engaging full six-wheel drive crawl mode automatically when required.

Guy has had both of his Terex Trucks ADTs at Omaio for three or four months now. With six team members here, Guy also has operations running elsewhere; when it comes time for one or both Terex Trucks TA300’s to be transported, their dimensions and operating weights mean that he can transport them without the need for a pilot vehicle, reducing complexity yet again.

"We’re really happy with these trucks, as well as the Porter Equipment support we’ve had to get them here and working," Guy concludes. It would appear the load-hauling abilities and practical comforts of Terex’s TA300 ADTs have a way of levelling out even the steepest terrain. No wonder Mikey seemed to regard my amazement at the altitude with a bit of bemusement.

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