Terex adding its two heaviest articulated trucks to the popular Generation 7 line-up, to ensure that the trucks were able to exceed the expectations of customers in this competitive sector. Now Terex has unveil this range-topping duo, which feature an all new operator’s cab that will be adopted by the smaller models in the Generation 7 range.
This new, centrally-mounted cab replaces the side-mounted operator station that was previously used on the TA35 and TA40. It benefits from increased internal space with larger glazed areas and its central mounting makes it easier for operators to maneuver the machine on site.
The cab has a completely new automotive style dash, with a Siemens VDO flat screen information panel at its centre. The screen is flanked by two large clear dials for travel speed and engine revs, with smaller dials for oil temperatures situated below.
This clear dash layout is easy to read and use, with the central screen offering additional information on systems and component condition when required. It provides productivity and operating data and can be used by service technicians to assist with fault diagnosis.
The ergonomic design of the TA cab puts all of the controls literally at the driver’s fingertips, with retarder, gear selection lever and handbrake in a curved grouping to the right of the driver’s seat.
The operator is well cared for, with air-conditioning, a fully adjustable suspension seat and a reach and rake adjustable steering column. A stereo radio/CD player is also included in the standard specification.
As the cab is the operator’s office throughout the working day, there is plenty of storage space, with a coat hook behind the driver’s seat, storage box beneath the passenger seat, deep door pockets and cubby holes above the front windscreen. Both the TA35 and the TA40 are powered by Detroit Diesel 60 series engines, while the smaller TA25, TA27 and TA30 models have the latest Tier 3A Cummins diesel engines.
The electronically-controlled 14 liter Detroit engine meets Tier 3A European emissions legislation, while providing similar levels of performance to the previous TA35 and TA40 trucks. In the TA35 that equates to 400hp (298kW) and 2,000Nm (1,475lb ft) of torque, while the range topping TA40 has a powerful 450hp (336kW) available, along with 2,100Nm (1,548lb ft) of torque.
The biggest change to the driveline comes behind the engine however, where Terex has moved away from the remote-mounted ZF310 transmission, in favor of an Allison HD4560. This transmission is now mounted directly to the engine, the benefit being that it has now been possible to fit a remote two-speed transfer box after the transmission, effectively doubling the number of gear ratios available to the operator.
Top speed of the TA40 is 60km/h in the upper range, with sixth gear equal to 37.5km/h in the lower range. The TA35 has a top speed in the high range of 53.9km/h.
The operator will experience far smoother gear shifting, both up and down the gearbox, and the transmission offers increased reliability due to the strength of its construction. To demonstrate this a 10,000 hour/three year warranty is now offered on the driveline.
A greater benefit to the operator is improved retardation, both from the new oil-cooled service brakes and from an integral retarder working on the output shaft of the transmission. In addition, the Detroit engine is equipped with an equally effective engine or ‘Jake’ brake, which closes the valves and in effect makes the engine work like a compressor, providing additional retardation. Unlike the previous TA40 and TA35, both of these retardation systems can be used separately or in conjunction with each other. The operator simply switches the engine brake and the retarder on, with switches on the dash, and then every time their foot comes off the accelerator pedal the two braking systems come into play.
The retarder has six positions, controlled by a lever to the right of the steering wheel. The engine brake has three positions, working on two, four or all six cylinders, controlled through the switch to the left of the steering. When used together, the engine brake and the retarder will virtually bring the truck to a halt, even fully laden on the steepest descents, prolonging service brake life and reducing operating costs.
When the secondary retardation systems are used correctly, service brake discs are expected to last up to 15,000 hours on the new TA trucks, as the retarder and engine brake will carry out most of the braking in normal use.
The front axle of the TA35 and TA40 has been moved further back on the chassis, now riding on a four-point suspension system. This suspension has revolutionized the ride in the cab, and prevents any dipping of the cab to the side when the steering is fully turned. In combination with lower noise levels and smoother gearshifts, this makes the TA35 and TA40 more comfortable to drive, allowing the operator to use more of the performance, more of the time.
Engine oil changes are extended to 500 hours, with transmission oil change intervals now set at 3,000 hours. All of the hydraulic services now run through a single valve block, increasing efficiency, and there is a centralized bank of test points beneath a steel cover to the left of the cab for the service technician.
An impressive level of service access was high on the list for the designers. The large single piece engine cover tilts forward using an electric motor, and with four bolts removed it is possible to tilt the cab sideways with a hand pump fitted beneath the bonnet. Tilting the cab allows unparalleled access to the transmission and hydraulic valve block.
At the front of the engine bay Terex has developed a highly effective cooling pack arrangement. The TA35 and TA40 use twin hydraulically-driven cooling fans, mounted side by side in front of the engine. Rather than having one radiator behind another, Terex has placed all of the cooling cores side by side in two main packs across the front of the engine bay.
The left hand bank includes the transmission oil cooler, retarder oil cooler and the service brake oil cooler, while to the right there is the engine coolant radiator and the charge cooler for the turbocharger.
The benefit of this arrangement is that none of the cooling cores is taking hot air from another radiator in front of it, all getting equal access to the cooling fans. In addition it is easier to clean any dust or debris from the cooling packs as they are easily accessible, both from the front of the truck and from inside the engine bay.
The trucks are permanent six wheel drive with a differential between each axle to prevent wind-up. All three axles have automatic limited slip differentials and the leading rear axle has a drive-through differential which, along with the drop box output differential can be locked using a single switch on the dash.
The all-welded high grade steel body remains virtually unchanged from the successful predecessors, offering a heaped capacity of 21cu m on the TA35 and a class-leading 23.3cu m on the TA40. Maximum payload is 38 tonnes on the TA40 and 34 tonnes on the TA35.
The TA25, TA27 and TA30 all now feature Tier 3 Cummins diesel engines. A QSC8.3 in the smallest truck offers 300hp (224kW) and 1,356Nm (1,000lb ft) of torque. The QSM11 in the two larger models produces 365hp (272kW) in the TA27 and 385hp (287kW) in the TA30.
These trucks also feature a new engine retarder and the TA27 and TA30 have adopted the multi-plate oil-cooled disc brakes in all three axles. The TA25 retains its conventional dry disc brakes. Both the TA27 and TA30 also ride on new independent front suspension.