Freightliner’s Medium-Duty Makeover
A major update to M2 and SD models with new Plus series sees enhancements to the interior and electrical systems.
Circling the highway loop at the American Center for Mobility in Ypsilanti, Michigan, the enhancements Freightliner engineers made to the new Plus series medium-duty and vocational trucks are evident. The cab is more comfortable and noticeably quieter than previous M2 and SD models, and active-safety demonstrations highlighted a first for these trucks – the Detroit Assurance 5.0 suite of safety and connectivity systems.
The M2 106 Plus (Class 6-8), M2 112 Plus (Class 8), 108SD Plus (Class 7-8) and 114SD Plus (Class 8) also feature a new electrical architecture with additional electronic control units, enabling the enhanced safety and connectivity features. The new multiplex electrical system also could help enhance the eventual electrification of the models.
Some things did not change from the previous model. Greg Treinen, product marketing manager, Heavy Vocational at Daimler Trucks North America, noted carryovers such as the 2500-square-inch windshield and sloped hood for visibility, the 55-degree wheel cut for maneuverability that is critical for pickup and delivery applications, the steel-reinforced aluminum cab, frame rails, clear back of cab and the routing and clipping that was updated a few years ago. “While the Plus series represents a major change, there has been an evolution over time,” he said.
Engineers emphasized electrical-component placement to improve durability. The power distribution module was relocated from the fender to under the hood on the firewall, where it’s less prone to road vibrations. The transmission control module also was relocated for additional protection. The electronics are protected in a IP69K enclosure. “There’s a couple of other key aspects that we moved behind the dash, so we really focused on placement of electrical-system components to reduce instances of downtime,” Treinen said.
“Why the Plus series?” Aaron Scates, VP of Vocational and Medium-Duty market development at Daimler Truck North America, asked to begin his presentation at ACM. Because customers asked for it. The M2 was introduced more than two decades ago and has been a consistent best-selling medium-duty product for DTNA. The SD model, a leading product in the vocational market for DTNA, launched about 10 years ago. “Over the years we’ve made incremental improvements,” he said. “More recently we’ve gotten customer feedback needing to make a major leap forward in terms of technology and features.”
Active safety and connectivity
Already available in other DTNA products, Detroit Assurance 5.0 is now available across Freightliner’s entire vocational and medium-duty truck lineup. With its new electrical architecture, Plus-series trucks give customers access to the safety systems not only by selecting the Detroit DD13 Gen 5 engine with DT12 or DT12-V (vocational variant) automated manual transmission, but also “for the first time in any DTNA product” when spec’ing a Cummins engine.
“If you’re a fleet and you have different needs in terms of powertrain, you’ll now be able to get the same performance and experience and also train your drivers in the same way about how to use the equipment regardless of powertrain choice,” Scates said. Previously, Cummins engines were paired with WABCO or other third-party active-safety systems.
Depending on truck model, the Plus series lineup offers the Cummins B6.7, L9 and X12 diesel engine options as well as L9N and ISX12N natural-gas engines. Eaton manual and automated manual transmissions, as well as Allison automatic transmissions, are also available.
Active Brake Assist 5 provides full braking when approaching stopped or moving vehicles and pedestrians. On the ACM test track, a ride-along demo illustrated the effectiveness of the ABA5 system, bringing the M2 Plus truck traveling at 35 mph (56 km/h) to a complete stop just inches away from a static obstacle in the road.
“In the vocational market, safety is not just becoming cost of entry; for many customers it’s required to do business,” Scates said. Other safety features include Lane Departure Warning and optional Side Guard Assist, which informs the driver when a pedestrian, object or vehicle is on the passenger side of the vehicle. An amber light on the A-pillar warns the driver when an object is there; the light turns red and an audible alert sounds if the driver attempts to change lanes or make a turn. There is no active steering assistance on M2 and SD Plus models.
Adaptive Cruise Control works down to 10 mph (16 km/h), and Intelligent High Beam Assist automatically turns high beam off when encountering oncoming vehicles. Outfitted with the Detroit Connect suite of connectivity systems, Plus series fleets will receive key information about vehicle performance. The Virtual Technician remote diagnostic service informs fleets within minutes of a fault event of its severity, and when, where and how to best fix the issue. Remote Updates uses over-the-air programming capabilities to make engine parameter and other updates.
Detroit Connect Analytics provide users with on-demand, automated analysis, identifying behaviors and trends, and providing actionable insights on fuel consumption and safety performance data. Safety Event Viewer enables visibility into driver safety performance, notifying fleets of collision mitigation events.
A major focus for engineers was TEM (truck equipment manufacturers) integration and upfit efficiency. Again, the new electrical architecture enables Freightliner to offer the QuickFit System and programmable modules together with the CHEC Tool. The CHEC Tool provides a user-friendly interface to view and modify electrical configurations and change parameters in minutes, according to DTNA.
“That allows TEMs to integrate their software body controls, configure switches, create interlocks, all located on our architecture,” Scates said. “The advantage for a TEM who works with DTNA on multiple product lines is really the upfit methodology. The way that they connect to the vehicle both in terms of software and also their electrical connections will be common between our products. That’s a huge improvement in upfit efficiency.”
“You can also imagine the potential here that we can now host TEM software and really make their connections to our vehicles, and the way that they program our vehicles, plug and play,” Scates added. “That [plug-and-play] potential can’t be overstated.”
Quieter, more comfortable interior
A marked move to “automotive style” interior features stem from customer feedback, according to Treinen, with the goal of helping to attract and maintain drivers. Standard LED lighting and upgraded seat materials that take ergonomic cues from the Cascadia are examples of this update. The seats also recline further and have greater travel by a couple additional inches.
NVH reduction was another focus for engineers. More-robust plastic materials and better fit and finish for the door panel and dash help to reduce squeaks and rattles. Standard insulation in the roof and backwall insulation on the premium package help to reduce cab noise by 1 dB. The NVH enhancements were especially noticeable when driving on ACM’s off-road course.
Controls placement plays a big role in improved ergonomics for operators. Electric door and lock switches were moved from the B-panel to the doors, as is customary in passenger vehicles. Speakers also were relocated from the dash to the doors to improve audio quality, which was a “key piece” of customer feedback, according to Treinen. The steering wheel now features integrated multifunction buttons.
The 5-inch display used in other DTNA models is now found in the M2 and SD Plus trucks. The display shows trip information, fault codes, Detroit Assurance safety information and warnings, Adaptive Cruise Control, and PTO control logic. The highly configurable dash panel increases the amount of space by 2.5 times that TEMs can utilize for programmable-switch integration.
Production of the Plus series is expected to begin Q3 2023 at the DTNA Mount Holly (North Carolina) and Santiago Tianguistenco (Mexico) truck manufacturing plants.