LAS VEGAS, Nev. — Navistar showcased improvements to its severe-service International WorkStar and PayStar trucks this week at World of Concrete.

Changes to the WorkStar include: the 7600 and 7700 models have been combined into one model with two versions, the 7600 SBA (46-inch set-back axle) and 7600 SFA (30-inch set-forward axle) with both models featuring a new 113-inch BBC for better cooling; a crew cab configuration is now available in heavy-duty diesel models with front axle ratings up to 18,000 lbs for select applications; all-wheel drive is now available on models with up to 18,000-lb front axles on mid-range diesel configurations; steerable 20,000-lb lift axles are now available from the factory; and aluminum fuel tanks are standard for lighter weight and better corrosion resistance. The HVAC system has also received some attention to improve its effectiveness and durability, the company reports.

The PayStar, meanwhile, receives: standard electronic stability control; 8,000-, 13,200- and 20,000-lb lift axles available from the factory; 10.25×3/8-inch frame rails are now standard on the PayStar 5900 SBA; availability of the MaxxForce 11 and 13 diesel engines in the near future; and availability of the MaxxForce 15 in late 2010.

“We continue to focus on meeting the needs of vocational customers by delivering innovative, best-in-class products for a wide range of severe service applications,” said Jim Hebe, senior vice-president, Navistar’s North American sales operations.

Of course, Navistar also touted its EGR-based EPA2010 emissions solution which does not involve exhaust aftertreatment.

“Our MaxxForce Advanced EGR engines truly differentiate ourselves from the competition,” Hebe said. “More than any segment in commercial trucks, severe service truck customers don’t want to deal with the uncertainty and inconvenience of SCR. With our WorkStar and PayStar trucks integrated with MaxxForce Advanced EGR engines, they won’t have to.”