Navistar International has unveiled its new Class 4 and 5 TerraStar model, calling it a "powerful, rugged and reliable work truck" and, during a press conference at the National Truck Equipment Association's Work Truck Show

in St. Louis, noted that it will be sold solely as a commercial vehicle. It will be standard with a redesigned MaxxForce 7 V-8 diesel mated to a 5-speed Allison 1000 automatic transmission.

The TerraStar will seek the business available since General Motors abandoned much of the medium-duty market last summer, and answers increasing demand for products in the growing Class 4-5 segment, said Jack Allen, president of Navistar's North American Truck Group. GM had 23 percent of the market and Sterling Truck, which ceased operations a year ago, held 3 percent.

"We see the market is in turmoil and represents a great opportunity for us," Allen said. Navistar will seek GM and Sterling sales and try to capture others from Ford, the market leader with 60 percent of the business. Designers and engineers therefore developed the TerraStar in one year by basing it on existing components in the International product line, including the Diamond Logic multiplex electrical system.

The TerraStar uses the same heavy duty-based cab as other International medium-duty trucks, and sits on a frame derived from the now-discontinued CF low-cab-forward model, executives said. The frame dips down under the cab to allow it to sit about 4 inches lower than the next-biggest model, the DuraStar 4100. Though it sits 4 inches higher than a comparable Ford F series truck, the International includes a low outside step to help drivers climb inside, Allen said. The wide cab easily accommodates three large men and has a large windshield and side windows for excellent outward visibility.

A full tilting hood allows easy access to the engine and underhood accessories and electrical parts. There sits the MaxxForce 7, whose block is now cast in compacted graphite iron for greater stiffness and lighter weight than grey iron. It has two simple turbochargers, Advanced Exhaust-Gas recirculation that needs no urea aftertreatment equipment, and Navistar's own electronic controls and programming software.

The updated diesel has ratings of 240, 260, 280 and 300 horsepower with 560, 600 or 660 pounds-feet of torque. It is also standard in International's DuraStar 4100, 4300 and 4400 trucks. The Diamond Logic electrical system ties the engine to the chassis and, with its multiplexing feature, allows quick and easy hookups of switches to body tools and accessories.

TerraStar will go into full production this fall at Navistar's plant in Garland, Texas. It will initially be available as a 2x4 with a regular cab and a 107-inch bumper-to-back-of-cab dimension. An extended cab and four-door crew cab will come later this year, and a 4x4 chassis next year. Work-ready trucks with various specialty bodies are a possibility later, executives said.

More info: www.Navistar.com