LAS VEGAS — In a step toward more integrated drivetrains in Kenworth and Peterbilt trucks, Paccar announced a new 40,000-pound tandem axle that saves weight and improves fuel economy.

This axle is “really helping us make steps toward an integrated powertrain,” Landon Sproull, Paccar vice president, told reporters at the American Trucking Associations Management Conference & Exhibition.

The new axle is designed for line haul, regional haul and pick-up and delivery customers, rated at 40,000 pounds and supporting a gross combination weight of 80,000 pounds. It offers ratios from 2.47 to 3.70 with engine torque compatibility up to 1,650 lb-ft and multi-torque rating compatibility up to 1,750 lb-ft.

The Paccar axle features a pinion-through-shaft design that simplifies power flow in the axle for maximum efficiency. A laser-welded carrier design eliminates internal fasteners, and reduces oil churn and weight. Overall the axle offers up to 150 pounds of weight savings, according to the company. Sproull did not specify the fuel economy improvements, noting that it would vary by application.

Kenworth and Peterbilt will begin offering the axle to customers in January 2017. It carries a warranty of five years or 750,000 miles.

Also available in Kenworth and Peterbilt trucks in January will be new power, torque and fuel efficiency enhancements to Paccar MX-13 and MX-11 engines for North America. Nearly 50% of Peterbilt and Kenworth heavy-duty trucks currently are produced with Paccar MX engines, according to Sproull.

Paccar increased the MX-13 engine’s output to 510 hp and 1,850 lb-ft of torque and increased the MX-11 engine’s output to 430 hp and 1,650 lb-ft of torque. The enhanced Paccar MX-11 engine also adds a new 335 hp and 1,150 lb-ft torque rating in the lower end of the power range. Paccar’s MX engines now deliver peak torque at 900 rpm for the majority of engine ratings, supporting increased performance and driving flexibility and supporting downspeeding strategies for fuel economy. 

The 2017 MX-13 and MX-11 engines include a new single cylinder air compressor, variable displacement oil pump, and variable speed coolant pump for better fuel economy than the previous engine design.

The MX-13 is also 50 pounds lighter. The weight savings primarily came through changes in the accessories, Sproull explained, including a new high-performing turbocharger, with a different turbo for engines up to 485 hp and a different one for 485 hp and beyond.

The new MX-13 and MX-11 engines extend oil and fuel filter change intervals from 60,000 miles to 75,000 miles.Also new is a single canister aftertreatment system that reduces weight by 100 pounds, improves the performance of the aftertreatment system, improves serviceability and lengthens service intervals, according to the company.