Peterbilt Highlights Efficiency with 579 Epiq
During its presentation at the 2015 Mid-America Trucking Show, Peterbilt reported up to a 14% improvement in fuel efficiency reached with its Model 579 Epiq.

Photo: Peterbilt

Photo: Peterbilt
During its presentation at the 2015 Mid-America Trucking Show, Peterbilt reported up to a 14% improvement in fuel efficiency reached with its Model 579 Epiq. The inspiration came from technology used on Peterbilt's EPA SuperTruck project.
“The 579 provides for customers like no other product in Peterbilt’s history,” said Scott Newhouse, chief engineer, Peterbilt. “We raised the bar again with our 579 Epiq model.”
Now in production, the 579 Epiq features aerodynamic design elements, powertrain efficiency, and fuel-saving technology borrowed from the design elements incorporated into the SuperTruck, which achieved 10.7 mpg after extensive field testing, to reach the 14% gain possible with the new Model 579 Epiq.
The 579 Epiq includes Apex, an optimized drivetrain that pairs the Paccar MX-13 engine with the Fuller Advantage Automated Transmission.
“We developed proprietary control logic that provides precise communication between the MX-13 and the Advantage transmission for a fully integrated powertrain that delivers superior fuel economy,” said Newhouse.
Among the newest elements of Epiq are:
A roof fairing bridge that reduces the gap between truck and trailer;
Enhanced chassis fairings that minimize the opening in front of the tandem axle;
Rubber wheel closeouts on the front axle;
A durable bumper dam that reduces aerodynamic lift and drag; and
A bumper-to-hood seal that redirects air around the truck.
“We’ll expand the 579’s versatility even further with the introduction of our new 58-inch sleeper, engineered for weight-conscious short regional haul operations, the new sleeper reduces weight by up to 100 pounds, while including all the driver-pleasing amenities,” added Newhouse.
The new sleeper will go into production in the fourth quarter of 2015, and will be available in both low- and mid-roof configurations.
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