Kenworth has announced the that the Paccar Powertrain Fuel Economy Package will be available as a spec on T680 model trucks beginning next year. According to Kenworth, the new package combines the fully integrated Paccar Powertrain, including the Paccar MX-13 engine with a new 405-hp at 1,650 lb-ft of torque rating, Paccar 12-speed automated transmission, PACCAR 40K tandem rear axle, and enhanced Kenworth predictive cruise control technology.
Kenworth to Offer Paccar Fuel Economy Package on T680 Models
A new, fuel economy optimized powertrain spec will be available for Kenworth T680 models beginning next year.

The new Paccar Fuel Economy Package available on Kenworth T680 models features a 405 horspower Paccar MX-13 diesel engine.
Photo: Kenworth
According to Kenworth, this package includes a new version of the MX-13 engine, featuring a new torque curve that further refines the engine’s fuel economy performance in line-haul and regional haul applications by lowering the engine’s horsepower rating while maintaining its torque.
“This combination maximizes fuel economy and offers excellent performance for our customers,” said Kurt Swihart, Kenworth marketing director. “One of the bigger contributors is the deeply integrated predictive cruise control function, which varies the vehicle’s speed over rolling hills without reducing the average vehicle speed. The transmission software is also optimized for the PACCAR MX-13, allowing for lower engine RPMs at cruising speeds. At Kenworth, we’re continually researching ways to enhance spec’ing to find the best fuel economy combination available. The new 405-horsepower rating is just one example.”
The PACCAR Powertrain Fuel Economy package will be available in the first quarter of 2019.
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