Kenworth T659 Review

Name: Kenworth T659 Review
Brand: Kenworth

We travel to Far north Queensland to check out some really heavy-duty rigs

Heading up the Lynd Road in Far North Queensland has, until recently, been a treacherous ordeal along a narrow pot holed road. Today, it’s all bitumen and there are fewer potholes, nevertheless it has still retained some of its notorious heritage which still tests both the men and machines that dare to venture up its path.

The Lynd Road, as the locals call it, stretches from Charters Towers, 260km north to the Lynd Oasis Roadhouse where it forks. To the left, it leads north-west up into the Gulf Savannah country and to the right it heads north east onwards to the mining town of Mt Garnet a further 180km up the road.

The darkness of the night gradually subsided as sun’s gentle rays began to peer over the horizon when I veered off to the right at Lynd Junction. I was making good time to arrive punctually at my prearranged mid-morning rendezvous with Oakdare Holding’s Michael Connolly at Mt Garnet to see first-hand the efficiencies they’re getting from their Azmeb quad door-side tippers.

Michael is the Business Development Manager for Oakdare Holdings – a bulk haulage and civil construction operation that includes the Mt Garnet Operation. Michael’s parents Wes and Kristine founded the company in December 1990 with the amalgamation of W & K Connolly Earthmoving and Jack’s Livestock and General Transport.

Like many self-made family businesses, Oakdare Holdings prides itself on service and reliability as well as the ability to provide unique transport solutions to their clients. One of their specialty services is their ability to work in remote locations at short notice, which includes the supply of a self-sufficient site camp and maintenance facility.

The Mt Garnet operation highlights this and looks after the transportation of approximately half a million tonnes of mined ore from the Surveyor mine near Lynd Junction to the Mt Garnet processing plant. Oakdare Holdings also hauls approximately 70,000 tonnes of processed ore from Mt Garnet on a grueling 560km trek via Charters Towers to the port in Townsville.

Glancing around the yard, it’s quickly apparent that high productivity combinations dominate this fleet. “There’s not a single-trailer outfit anywhere in the fleet,” Michael tells us.

These days, every combination in the fleet is either B-Double, road-train double, triple or quad, like the units operating on the Mt Garnet contract.

Across the fleet, Kenworth T650 series are effectively the sole choice of prime mover and Azmeb ‘door-side tippers’ and dollies the sole choice of trailers.

"We have more or less standardised on Kenworth’s T650 and now the T659 for the road-train side of our operation simply because they are such a reliable tough truck. We do a lot of work up in the top of the Gulf and Cape York and you really need rugged equipment to operate up there. The conditions are extremely severe," Michael added.

Cummins have been the preferred powerplant of choice in the Oakdare fleet and that goes way back to the days when you had a choice of three engines in a Kenworth. Again, however, Michael refers to the people factor as the critical contributor in the long-term relationship with Cummins.

"We’ve had a good run out of Cummins engines over the years and their service and parts availability up here is the remote area is first class," Michael said. "Cummins engines are a lot like Holden cars up here, you can always find someone who has a part that can get you out of trouble," he added.

The 600hp Cummins e5 engines that produce 2050 lbft of torque powers the company’s latest T659 Kenworths, the engine is coupled to an Eaton RTLO22918B transmission with Dana D52-190 rear axles all riding on Kenworth 6-Rod suspension. These heavy-duty Kenworths come standard with two CR Turbo 2000 air dryers with heaters and a Cummins 37.4cfm twin cylinder compressor.

Dual 356mm (13”) external Donaldson air cleaners with water-resistant elements, and 152mm (6”) diameter raised ducting, and intakes feed the Cummins plenty of air.

Up front is the heavy-duty King built Warrego bullbar, which has the addition of the optional fifth middle post for extra strength. "They’re great bullbars," Michael said. "As you can imagine we get a lot of animal strikes up here and they have saved us countless times."

Much like the Kenworth T659 the trailers are very versatile. They boast an extremely light tare weight, from 6.4 tonnes and can carry materials from fine concentrates to one-metre blast rock.

"We have 65 Azmeb door-side tippers and 40 Azmeb dollies," Michael explained.

The backbone of the trailer is the deep-dished cradle type-high tensile steel (800MPa) chassis producing a very light tipper chassis with a low centre of gravity. ?The cradled bowl-shaped body is made of Hardox 450 grade abrasion-resistant high-tensile steel that is free of body runners, stiffeners and cross members giving the body a very light tare weight.

Tipping is via two only, six-inch (150mm) double-acting hydraulic cylinders with door opening via linkages, which gives the fastest tip cycle of any tipper, we’re told. The door is over-centre locked when in the closed/travelling position. Doors are manufactured from Hardox 450 Grade or 5083 H116 Aluminium dependent upon client’s tare weight and application requirements.

The Azmeb door-side tipper has a single hydraulic ram construction, which lessens the need for extra controls and hydraulic circuits, in turn reducing potential downtime.

"The single ram design means that when the trailer tips, there is only one action for tipping and door opening combined, speeding up the overall process considerably," Michael explained. "The bowl floor design also aids this fast unloading process, as it reduces sticking and avoids product getting caught in the corners of the tub. Dependent on the hydraulic flow supplied, the whole load can be tipped in as little as 25 seconds."

A heavy-duty rubber hinge on the door is another unique feature of the product. “The rubber hinge is tough, durable, and isn’t prone to rust," Michael revealed. "It also saves on maintenance times as there are no grease points on the door hinge. But most importantly, with the rubber hinge they are watertight and that is critical in our operation here at Mt Garnet where we are carting hazardous ore products. We simply can’t afford any spillage."

Meanwhile, a continuous tub-to-chassis pivot bearing distributes loads evenly across the tub and chassis, resulting in low maintenance and trouble free operation.

"We exclusively use BPW axles in our trailer fleet and we have over 300 of them," Michael revealed. "We run the 120mm square axle and they more than stand up to the punishment they get here in north west Queensland.

"We specced our trailers with steel-spring suspension as they’re more reliable in the bush work we do," he added.

Purchasing quality equipment has certainly paid off in the long term for Oakdare Holdings too as Michael explains.

"We use to religiously turn our vehicles over around that one-million kilometre mark. However the economic down-turn made us rethink some of our business strategies and we opted to keep the trucks we owned longer, to assist with our cash flow.

"We spent a bit of money on them around that one-million km mark to give them a freshen up and now some of those trucks and trailers have over two-million kilometres and they’re going back and forth just the same as our new ones,” Michael added.

"It is that simplicity in maintenance and the durability we get from quality equipment that really drives our business forward," Michael concluded. "And that means we have good driver acceptance because without out drivers we would be going anywhere."

Truck Specs:

Model: Kenworth T659

Engine: Cummins e5

Horsepower: 600hp (447kW) @1850rpm

Torque: 2050lb/ft (2780Nm) @ 1100rpm

Gearbox: Eaton RTLO22915B 18-Speed

Chassis: Full-length double frame with sealant between rails

Air Cleaner: Dual 356mm Cyclopacs with raised air rams

Fuel Filter: Fuel Pro and fuel/water separator

Electrical: 160A isolated alternator & power distribution box

Front Axle: Meritor MFS73 7.3 tonne capacity

Front Suspension: 7.2 tonne multi leaf