Spec’ing trucks is an ever-evolving process

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Getting your truck spec’s right depends on your application, first and foremost, according to fleet professionals presenting on Truck Spec’s 2022 at the Technology and Maintenance Council Fall Meeting in Cleveland, Ohio, on Sept. 14. But, it is also a constantly evolving process thanks to the steady flow of new technology coming into trucking today.

One of the most recent technological developments has been downsped drivetrains, said Kris Ptasznik, heavy duty on-highway product manager, Cummins.

Kris Ptasznik with Cummins, cautioned TMC attendees that selling trucks equipped with manual transmissions can take longer because fewer drivers today are trained and have endorsements to use them. (Photo: Jack Roberts)

Downspeeding, he explained, allows trucks to cruise at lower rpm thanks to faster axles ratios. But it’s not for everyone. “If you’re on the highway and at cruise speed 90% of the time, downspeeding is a natural fit for your application. If you’re on the highway, say, 80% of the time, and on two-lane roads the remainder of the time, then they are some advantages to downspeeding, but they are balanced by the limited resale value you’ll have for that truck when it’s time to dispose of it.”

Another critical question fleet managers must consider is how much horsepower they actually need to get work done with their trucks, Ptasznik added. “If you’re running on flat ground at cruise speeds, what does 500 horsepower give you other than a driver who gets to tell people he’s got 500 horsepower under the hood?”

For the most part, Ptasznik said, proper horsepower spec’s come down to geography and application. “Big bore engines typically have better resale value,” he noted. “And they offer better climbing ability and engine braking for driving in hills and mountains. On the other hand, if you take weight out of the engine, you can haul more stuff. And smaller engines mean smaller upfront acquisition costs.”

Another fairly recent spec’ing development has been the choice between manual gearboxes and automated transmissions (AMTs), Ptasznik said. “AMTs have the downside of higher cost,” he noted. “But they have a much faster ROI than manuals through reduced fuel costs.”

But interestingly, he added, AMT popularity has exploded over the past several years. And, as a result, many commercial drivers today trained on AMTs and cannot drive manual transmissions.

“So understand that if you spec’ an manual, it may take you a longer period of time to sell that truck later on, because you’ll have to wait for a driver (or a fleet) with a manual transmission endorsement to buy it.”

Joe Eilerman, engine product manager, Daimler Trucks North America, said that advanced driver safety systems (ADAS) and collision mitigation systems (CMS) began life as two separate, but complimentary technologies. But now, he says, those lines are blurring when it comes to spec’ing driver safety and assistance systems.

“The two systems are becoming increasingly integrated,” he said. “And we’re seeing more and more sensors on trucks now that ‘talk’ to each other with greater confidence and fewer false positives than in the past. We’re also starting to see more sensors now covering the sides and rear of the trailer, as well.”

Another noteworthy new spec’ Eilerman pointed to are rearview camera systems, which take the place of traditional rearview mirrors to decrease aerodynamic drag and increase fuel economy. “I’d advise you to keep an open mind about these systems,” Eilerman told the audience. “Because they offer significant fuel savings.”

Lee Long, director of fleet services, Southeastern Freight, stressed the importance of collecting data on all facets of your operation and using it to drive your future spec’s.

“Everything we do at Southeastern is driven by data,” he said. “Beginning in 2014, we began gathering data on both engine horsepower and transmissions and eventually changed our spec’s based on our findings. We went from a 10-speed to a 12-speed automated transmission because the testing showed we were getting another level of performance with those units and a better performing unit all the way around.”

Long also stressed the importance of involving your technicians in the spec’ing process.

“Technician acceptance of new technology and products is critical,” he said. “They’re the ones who will have to keep the trucks running. So, you need to have them weigh in on the repair process in general and how easy new technologies or products are to repair. And it’s the same thing with drivers. Make sure you communicate what you want to do and why with new technology or products. If you do that, you’ll find that they’re pretty accepting of the changes you want to make.”

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Jack Roberts has been covering the North American trucking and transportation industries as a journalist since 1995. A licensed commercial driver, Roberts has emerged as a leading authority on new and advanced logistics and vehicle technologies, including autonomous vehicle systems, battery-electric trucks, and hydrogen fuel cells. Roberts is a graduate of the University of Alabama and lives and works in Tuscaloosa, Alabama.

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