Mack Trucks has achieved what it calls a breakthrough in engine technology for the vocational market aimed at satisfying the Environmental Protection Agency’s emissions regulations going into effect in October.

Mack, the longtime dominant truck manufacturer in the vocational segment of the heavy truck market (construction and refuse), says the new technology will allow it to meet the stricter emissions requirements while matching the specific demands of vocational customers.

The foundation for Mack’s EPA ’02 solution is a new platform of diesel engines built on its Application Specific Engine Technology (ASET). While all ASET engines will rely on exhaust gas recirculation (EGR) to reduce emissions, the vocational design breakthrough comes in the form of internal-EGR.

A technology allowing a percentage of exhaust gases to remain in the cylinders of the engine from one combustion cycle to another, Mack says this approach provides a consistent level of emissions benefits and performance in the varying and often harsh environments in which vocational trucks operate.

Mack insists its I-EGR will far surpass the industry-typical solution of cooled EGR in a stop-and-go duty cycle, over shorter distances and where operational hours are a more important concern than miles travelled.

“We’re still five or six months away from the deadline,” says Mack Trucks president and chief executive officer Paul Vikner. “So we’ve not finalized our pricing.”

He does however expect there will be a $3,000 to $3,500 premium on the new engines, but adds that Mack’s pricing will be competitive with the rest of the industry.

“We’ve got to pass on to the customers what this technology cost us,” says Vikner. “Mack can’t absorb those costs.”

This very dear technology, in the case of ASET engines ticketed for vocational applications, centres on optimizing the flow of exhaust gases through the system, in order to make it possible to retain a precise amount of gases in the cylinders for further combustion. That was accomplished through a new camshaft, advancements to the valve system, and precision machining of the exhaust ports to maximize aerodynamic flow.

“Mack does not believe that one EPA ’02 solution is the answer for all trucking applications,” says Steve Homcha, Mack executive vice-president of Class 8 programs.

Mack vehicles featuring I-EGR engines will roll out as of Oct. 1, and will include: the new Mack Granite Series, as well as Mack RD6, MR, LE, DM and RB models. Seven engines will be available with varying horsepower ratings, including three Maxidyne models (a 300-horsepower, and new 335 and 370 horsepower versions) and four Econodyne (350, 400, 427, and 460E horsepower) models. Ramp-up production begins in June.