Allison Transmission partnered with Cummins to test the new Cummins X15N 15-liter natural gas engine paired with the Allison fully automatic transmission. California-based bulk cement hauler Sandman completed more than 50,000 miles with the powertrain combination and reported significant improvements in fuel efficiency and performance.

Allison said the test vehicle, a Peterbilt tractor pulling double trailers of bulk cement, demonstrated the impressive performance and productivity of the X15N engine and Allison transmission combination.

“More than 20 years ago, we integrated Allison fully automatic transmissions, which changed the world for our drivers who haul 80,000-pound loads in stop-and-go traffic between San Jose and San Francisco multiple times a day,” said Victor Landaverde, fleet manager, Sandman.

Landaverde said his company was thrilled with the performance of the Cummins X15N engine paired with the Allison 4000 Series transmission and the potential impact it could bring to Sandman’s fleet of over 100 Allison-equipped natural gas trucks.

“The field testing has been flawless over the course of 50,000 miles, and in addition to achieving excellent fuel efficiency, the enhanced engine braking and consistently stronger power during shifting have significantly improved our operations,” Landaverde added.

Allison said the 4000 Series transmission is designed to deliver both performance and fuel efficiency. Its torque converter multiplies engine torque to significantly improve startability, drivability, and overall productivity.

Savings with the X15N with the Allision Transmission

Pairing the 4000 Series with the X15N, which is 500 pounds lighter than the diesel version of the 15-liter engine, will deliver additional fuel savings and emissions reductions for fleets. Allision said it also can reduce the total cost of vehicle ownership while supporting corporate social responsibility objectives.

The 4000 Series transmission used in Sandman’s trial is also calibrated with FuelSense 2.0, which is a unique set of software and electronic controls that provide quantifiable fuel savings of up to 6%.

“Allison fully automatic transmissions are fuel agnostic, meaning they can pair with multiple energy sources, including diesel, natural gas, electric hybrid, fuel cell, and battery electric. As the industry continues to evaluate electric vehicle technology and works to overcome the hurdles facing this technology adoption, more customers are expected to adopt alternative fuel engines as a solution to meet increasing emissions stringencies,” said Rohan Barua, vice president of North American sales, global channel and aftermarket, Allison Transmission.