Sterling Trucks
When a truck manufacturer announces a major product change, most of the time you can see it: a new headlight style, a splash of chrome, a roomier cab. But the latest A- and L-Line heavy-duty models from Sterling Truck have an upgrade thatís beneath the surface: the trucks are riding on a new chassis.

Featuring lighter frames, optional frame inserts, and additional suspension options, as well as new cab air suspension and a new cooling system, the HX chassis replaces the HN80 inherited when Sterling’s parent Freightliner LLC bought Ford’s heavy-truck works five years ago.

The HX was originally conceived to deal with the anticipated heat-rejection challenges of ’02 engines, and thus the need for more radiator capacity, but they never really materialized. The benefits seem real, regardless, and not just in cooling terms. New radiator options, all of them crossflow designs, include capacities of 1,000, 1,200, and 1,400 square inches. All of them feature a new mount with two or three bracing rods and new isolation system.

Still up front, the HX has an all-new accessory-drive system with all self-tensioning belts and the industry’s first ìscrollî-type air-conditioning compressor (made by Visteon). Used in high-end four-wheeler applications for several years, the compressor has fewer moving parts and “almost no wear points,” Sterling says, compared to piston compressors. Its simple design is 35 per cent more efficient, demanding less horsepower of the engine than ordinary compressors. Exclusive to Sterling for two years, it will be standard starting in 2004.

The HX frame is offered in section heights of 10, 11, and, for the first time, 13 inches. Body builders will be happy because every frame is now designed with the Optilock Chassis Grid System, a standard layout of frame holes at regular spacings on a grid pattern.

Front-axle suspensions now include taper-leaf springs up to 20,000-pound capacity, and multi-leaf designs good for 23,000. There are also maintenance-free options up to 14,600 pounds. New for A-Line on-highway trucks and tractors is the option of lightweight fibreglass composite springs that save 77 pounds. An AirLiner suspension, an existing Freightliner option, is also available for those who want air up front. The new TRW THP60 high-pressure steering box is a new, standard addition. Its compact size allows for greater wheel cut.

At the back end there are new Hendrickson options like Primaxx, an air suspension for vocational trucks, the Haulmaxx walking-beam, and an enhanced TufTrac two-stage suspension that improved ride quality in empty trucks. The only visible change to the HX chassis for a casual onlooker is the switch to cylindrical aluminum fuel tanks, now standard in 23-inch diameter, with 25 inches an option.

All Sterling trucks are built at the company’s plant in St. Thomas, Ont., which just built its 100,000th truck. For more information see your Sterling dealer or visit www.sterlingtrucks.com.