News

Aug 13, 2023

International pulls the sheet off of its S13 integrated powertrain

At a press event at the Las Vegas Motor Speedway, International introduced its

At a press event at the Las Vegas Motor Speedway, International introduced its S13 integrated powertrain. Developed in collaboration with the TRATON Group, the S13 integrated powertrain was created from a clean sheet design and consists of three distinct components–an engine, a transmission and an aftertreatment system–all designed and developed concurrently to ensure maximized compatibility and integration between systems.

In comparison to the first-generation International A26 engine specified with the 12-speed overdrive Eaton Endurant HD automated transmission, the S13 integrated powertrain provides a weight reduction of 52 pounds. When specified with the updated International LT Series aerodynamics package, the S13 Integrated offers up to a 15% gain in fuel efficiency.

Let's take a look at the components.

The 13-liter International S13 engine achieves advanced fuel efficiency and performance through combustion efficiency and a reduction of friction and pumping losses, the OEM noted during the press conference. The S13 engine operates on low revolutions and higher torque equating to fewer fuel injections and less fuel consumption. Designed with selective catalytic reduction (SCR) technology as the primary emissions reduction technology in mind, the S13 engine has no exhaust gas recirculation (EGR) cooler and flows 100% of the exhaust to the turbocharger in normal engine operating conditions. This process delivers more power and improved engine performance. Eliminating the recirculation of exhaust gas ensures a more complete fuel burn and allows cleaner air to enter the combustion chamber on the intake cycle to mitigate soot buildup.

Additionally, International noted that the S13 engine improves efficiencies in multiple areas. A fixed geometry turbocharger reduces system complexity and increases reliability. Low friction materials and finishes are used for the liners, rings and bearings. The design eliminated the downstream fuel injector and the high-pressure fuel pump operates at a lower pressure of 1,800 bar. Additional features include a dual overhead cam design and cast aluminum cam cover and oil pan, 23:1 compression ratio and a compression release brake for maximum engine braking power. The compacted graphite iron block of the S13 engine combined with a cast aluminum cam cover and oil pan help make this the lightest weight 13L powertrain available in North America.

When it comes to performance, the S13 engine has seven engine rating options, with a maximum 515 horsepower and 1,850 lb-ft of torque at 2,000 revolutions per minute (RPM) governing speed.

The first commercial transmission offered by International, the International T14 is a 14-speed fully automated manual transmission with an electronic clutch actuator. As part of the clean sheet design, shifting logic and integrated software controls maximize efficiency and performance resulting in gear shifting that is perfectly matched to engine revolutions, the OEM noted.

The T14 features a planetary gear set that supports a compact design and optional programmable reverse speeds. This transmission has two crawler gears for improved heavy load startability and low-speed maneuvering. Complete with deep low-end gearing and shifting smoothness, the T14 delivers efficiencies of a direct drive in an overdrive package.

The S13 Integrated Powertrain offers increased power with the full torque available at 900 RPM to support drivability. Drivers have shift-on-the-fly capabilities with Economy, Performance and Performance+ modes. Also included are intelligent shifting capabilities, like skip shifting and turning radius offsets.

In addition to multiple shifting capabilities, the T14 transmission includes options for low-speed maneuvering, hill hold, and initial vehicle movement modes.

The compact design of the Dual Stage Aftertreatment is purpose built with easy access for serviceability, as well as significantly improved emissions control and fuel efficiency. To keep temperatures at an optimal range and extend service intervals, the aftertreatment system includes a dual-stage SCR catalyst system in a one-box design.

Since an EGR cooler was eliminated from the combustion process, less soot and particulate matter are generated. This cleaner combustion cycle allows for extended service intervals and eliminates the need for active regeneration cycle and the diesel oxidation catalyst. By employing a design which eliminates the need for active diesel particulate filter regeneration, the Dual Stage Aftertreatment system saves fleets time and fuel.

The International S13 Integrated Powertrain includes dealer integrated software, built-in service products, repair maintenance contracts and other solutions available for International vehicles equipped with the new S13 Integrated Powertrain. OnCommand Connection, Navistar's connected services platform, will come standard and offer programmable parameters, over-the-air calibration changes and software updates. The powertrain's predictive capabilities help fleet owners and service managers stay ahead of potential service needs. International 360, Navistar's service communications tool designed to accelerate the repair process and streamline dealer communications, is also an available option to customers.

The S13 Integrated Powertrain is backed by North America's largest one-stop dealer network to support any service requirements. Navistar offers a five-year powertrain warranty, alongside a selection of additional warranties and extended service contracts.

The S13 Integrated Powertrain will be manufactured at Navistar's Huntsville Powertrain Manufacturing Plant in Huntsville, Ala.