Terex focuses on productivity with articulated dump truck

Diesel Progress North American Edition, August, 1999

The Terex Corp. is a $1.2 billion, diversified global equipment manufacturer based in Westport, Conn. The company is involved in a broad range of construction and mining-related capital equipment operating in two segments - Terex Earthmoving and Terex Lifting.

Terex Earthmoving manufactures and sells heavy-duty off-road trucks and high-capacity surface mining trucks under the brand names of Terex, Unit Rig and Payhauler, as well as large hydraulic mining shovels under the recently acquired brand name O&K. Terex Lifting manufactures and sells telescopic mobile cranes, aerial work platforms, utility aerial devices, telescopic material handlers and truck-mounted cranes, and related products, under the brand names Terex, Lorain, PPM, P&H, Marklift, Koehring, Bendini, Simon, RO, Telelect, square Shooter, Holland Lift and American Crane.

Although Terex has been building off-highway trucks at its U.K. plant in Motherwell, Scotland, for more than 40 years, it is a relative newcomer to the articulated dump truck (ADT) market, having built its first ADT, the 25-ton 32-04, in 1983. Nevertheless, the last 15 years have seen the company become one of the world's leading suppliers of articulated dump trucks.

Terex's ADT product line comprises four models with payloads from 25 to 40 tons, each model having a rugged design chassis and an all-welded dump body fabricated in high strength steel. The vehicles are powered by fuel efficient design, turbo/intercooled Cummins or Detroit Diesel engines built to meet all current regulations for noise and exhaust emissions. The engines drive 6 x 6 drive-lines via ZF powershift transmissions.

Depending on the model, axles are supplied by ZF or Dana Spicer. The Terex ADT range is expanded by special versions for forestry, coal and waste handling, and models developed to high-performance military specifications.

In the off-highway truck market where Terex's four ADT models compete, articulated trucks account for more than 70 percent of all sales below 55 tons. The growing acceptance of the ADT has led to increasing competition for sales of around 5000 units per year, particularly in the 22 to 27.5 ton sector, according to John Rotherford, the company's sales and marketing director.

"The 22 to 27.5 ton sector accounts for around 40 percent of all ADT sales and demands a very competitive overall package," Rotherford says. "Everything has to be just right - including the price, performance and reliability - but also operator comfort and delivery. We are, therefore, always looking for ways to improve our product offering in this sector."

This point is illustrated by the company's decision to replace its popular 25-ton payload 2566C ADT with the model TA25. The TA25 features a 25-ton payload with heaped capacity of 15 cu.yd. It boasts a refined design, quiet, ROPS/FOPS cab engineered to provide excellent operator comfort, an attribute backed by the high power, high torque, emissions-certified engine; electronic transmission control; and automatic limited-slip axle differentials.

The launch of the TA25 also coincided with several other announcements, including a new price structure and a three-year/5000-hour warranty for Terex ADTs. The line is also expected to benefit from a decision to introduce new product designations and a new white and grey color schemeinstead of the well-known all-green livery.

"We introduced the new livery and designations to increase the brand awareness of the Terex product line," continued Rotherford. "The new prices and warranty are a result of the improved design and production methods that have helped to improve our product quality and lower our manufacturing costs."

While Rotherford is confident that the new prices and warranty will increase the competitiveness of the Terex package, he is quick to highlight the benefits of the TA25's new design features, notably the new ZF transmission. Terex's tests have shown that the new transmission makes the TA25 much more productive.

Replacing the ZF 6WG 200 transmission used in the 2566C machine is the 6WG 210 unit from ZF's new Ergopower range of electronically controlled automatic powershifts. The new transmission is coupled to a Cummins 8.3 L, in-line, six-cylinder 6CTA8.3-C diesel engine rated 275 hp at 2000 rpm and a maximum torque of 828 lb.ft. at 1300 rpm - increases of 8 percent in power and 10 percent in torque over the 2566C ADT.

To attenuate both noise emissions and gaseous emissions via reduced fuel consumption, a modulating cooling fan that operates only when needed is fitted.

The 6WG 210 transmission consists of a torque converter close-coupled to a countershaft gearbox with integral output transfer gearing. Kick-down and manual override features are included, as is a torque proportioning output differential that transmits drive permanently to all axles and may be locked in difficult traction conditions. Six forward gears in a 5.56 to 0.61 ratio range give maximum vehicle speeds of 2 to 50 mph. Three reverse gears in a 5.56 to 0.94 ratio range give ground speeds of 2 to 31 mph.