Western Star unveiled its 2007 EPA emissions-compliant chassis as well as a variety of other product enhancements at the Mid-America Trucking Show.

The new chassis allows for improved cooling capacity and maneuverability, officials said. It was demonstrated at the show in the form of a 4900 EX with a Detroit Diesel Series 60 engine and 82-inch Stratosphere sleeper. The most significant chassis changes include an updated cooling package and new exhaust system. The design changes to the Western Star chassis will be applied to all 2007 models.

One of the most noticeable changes is an increase in rad size. Western Star has been able to accommodate the larger rad without making exterior changes to its hood and grille by adding a drop front frame casting for the axle configurations of all models.

On vocational trucks, raised radiator configurations with integral front frame extensions and a front engine PTO are available.

The changes made to accommodate the larger rad have resulted in some improvements to the front suspension, the company said. A 56-inch asymmetric spring now provides improved roll stiffness and better handling in turns due to a shortened front length.

New steering gears and optimized geometry also improve road feel, overall wheel cut and turning radius. Western Star will be adding the AF-18.0-5 18,000-lb steer axle to its family of axle offerings in combination with the 2007 updates.

Western Star also displayed an extremely lightweight model at its booth at the Mid-America Trucking Show. The 4900 SA weighed in at a TARE weight of under 14,999 lb., making it ideal for bulk hauling applications. The tractor was equipped with lightweight components including a 48-inch sleeper, MBE 4000 engine and aluminum front and rear disc wheels.

In other product news, Western Star announced it has developed a new butterfly hood for the 4900 SA with 123-inch BBC. The new hood improves access to the engine. The hood features hinged, removable side panels that fold up like butterfly wings for easier access to the engine, eliminating the need to tilt the hood forward.

The company says the new hood is best suited for heavy-duty vocational applications such as mining and oilfield. It will also be popular with snow plow operators, as the hood can be opened without interference from the plow.

Meanwhile, the 4900 FA with 123-inch BBC has been updated with an optional one-piece hood. The new hood has been introduced to eliminate split fenders with large diameter tires. It requires fewer parts and less maintenance, the company said.