That was why the design team focused so much on the aero aspects. The main thing the engineers sought to do was steer the wind.
“What you're trying to do with the air is either keep it from going under the truck, or you can direct it under the truck and control it as it goes down,” Duncan said. To direct the flow under the chassis, redesigned air dams were installed. When the air goes under the truck and trailer, that airflow pressurizes and reduces friction. The air comes out through narrow exhaust ports on the rear of the fender, interior to the new bladed signal indicators. The new flow also directs hot air away from the radiator and engine to improve cooling.
It’s better for air friction to direct the flow around the truck, keeping the stream connected in one continuous flow as it travels around and down the sides of the truck, which also reduces turbulence, Duncan explained.
The 2,385-mile trip in this version back home to Cleveland would be about $53 less, figuring diesel costs about $3 and assuming the 2017 version gets 8 mpg on average. On previous cross-country trips in my twenties, I would manually calculate my fuel costs every fill up to see how much overall I would spend, and how much would be left over for roadside souvenirs. For a trucker who drives 100,000 miles a year, this 6% represents a savings of $2,250 per year. And the mpg data for the Next Gen appeared at the top right of the display, so no manual math required. The top mpg Sturgess hit, by the way, was 9.9 mpg in the sleeper, and that was on fairly undulating terrain.
Speaking of terrain, due to the curved windshield, the visibility of the mossy emerald forests adorning those back roads was unobstructed, as was the view of other vehicles. Sensors also detect vehicles in the truck’s blind spot and flash a yellow caution signal on the relevant side-view mirror.
The Bendix Wingman Fusion advanced driver-assistance system, overall operated without issue. The lane-assist warning briefly popped off a few times around gentle curves on the road. The collision mitigation info was set up on the center of the display, showing the distance in seconds to the vehicle ahead at the current rate of speed. To test the system, Sturgess safely inched up to the sedan in front of us on an offramp to set it off. The whole display flashed yellow and beeped like holy heck. If a crash were imminent, it would have illuminated in red.
“Talking to drivers, what we found is they want the information to be displayed easily to them,” Duncan said. “They don't want to have to navigate around a bunch of menus. They want actionable information from the cluster.”
On our short drive, the equipment performed as expected, but if there were a problem, the display would be able to diagnose the issue and inform us if we needed to pull over or continue on to a repair facility. The powertrain, comprising the 2021 MX-13 (with 405 hp/1,750 lb.-ft. multi-torque rating) and Paccar 12-speed automated manual transmission, provided a seamlessly comfortable ride. As I was not behind the wheel I can’t comment on the responsiveness of the truck, but Sturgess operated it like he had been driving the Next Gen for years, though that could in part be due to the British expat’s cool, retired James Bondian demeanor.
The sleeper cab itself seemed similar to previous versions, though a new interior trim was added. With the Diamond VIT spec, the truck comes with tan upholstery and rich madrona inserts with diamond-pattern black stitching on the door pads. My neighbor with the 2020 T680 had mentioned how he would like more storage in the berthing area, and Kenworth did include a 5.5-in. storage shelf above the bottom bunk.
I can’t say for sure if in a few years my neighbor will trade out his classic model, which at least for the time being is still available for order, but the owner-operator is a stickler for fuel efficiency and recently has been commenting on rising diesel costs after his weekly trips. With a volatile energy future, that 6% could mean an increasing amount of savings in the next few years. Combine that with the safety features and great look of the truck, and it’s fair to say the T680 Next Gen will be a popular choice for Kenworth customers for the foreseeable future. It may even draw over some stalwarts from other OEMs. At the very least, the bold design will have every truck design engineer looking at new ways to improve aerodynamics and look good doing it.
