“Detroit components account for the majority of components spec’d in Freightliner and Western Star products. There are many advantages of a completely integrated powertrain to customers,” says Brad Williamson, manager, engine and component marketing, Daimler Trucks North America. “Detroit and Freightliner (and Western Star) engineers collaborate on projects to make sure every design works together and is optimized for fuel economy, performance, reliability and durability.”
An example is the integration of the Detroit DD15 engine with the DT12 automated mechanical transmission. “The DT12 transmission and DD15 engine integrate and leverage shift schedules only achievable by both components being offered by one manufacturer,” Williamson indicates. The Freightliner Cascadia Evolution equipped with the new DD15 engine, DT12 transmission and Detroit axles provides up to 7% better fuel economy than the previous Freightliner Cascadia powered by the Detroit DD15 engine.
“Another benefit of an integrated powertrain design is to be more cost efficient when emission and regulatory changes occur,” he continues. “These changes often require thousands of man hours to design, test, validate, optimize and integrate various components to deliver products that meet the customers’ needs. So instead of repeating this process with multiple brands of components, our integrated design makes the process less challenging and ultimately more efficient.”
Integration can also reduce downtime. “The Detroit integrated powertrain is monitored by Virtual Technician. [This is] Detroit’s proprietary onboard diagnostic system that monitors and communicates directly with truck owners on all potential and real issues,” says Williamson.
One stunning example of where integrated design is headed can be seen in the on-highway market with Daimler Trucks’ Predictive Powertrain Control. The truck’s cruise control system can see the topography of the road ahead. The powertrain then responds in the most fuel-efficient manner. While this technology sounds like science fiction, it is already in use.
Freightliner is currently using Predictive Cruise. Unlike a cruise control system that tries to maintain a given engine speed regardless of the terrain ahead, the Predictive Cruise uses GPS to look at the terrain up to a mile ahead. The system adjusts the actual speed of the truck for maximum fuel efficiency based on the terrain, while staying within 6% of the set speed.
Daimler Trucks North America worked with NAVTEQ, a provider of digital map data for location-based solutions and vehicle navigation. Using advanced digital map slope data from NAVTEQ, RunSmart Predictive Cruise combines high-precision GPS road coordinates with road grade data of more than 200,000 miles of the most widely used truck routes in the continental United States. ET