Kenworth just announced a significant upgrade to the nearly 9-year-old T680. I drove one of the original demonstrator versions of that truck at the Mid-America Trucking Show in March 2012, and have driven two versions since then, in 2015 and in 2017 with the introduction of the Paccar automated transmission.
Kenworth has produced more than 100,000 T680s since 2012, when it broke the mold with the 10-inch wider cab and 10% bump in fuel efficiency compared to its predecessor, the T660. But the truck has remained largely unchanged from the original, so this mid-life, next-generation upgrade was about due.
Standing across a parking lot, you’d be able to see the differences, but save for the narrower grille and the more chiseled look to the side fairings, the changes are subtle. The windward side of the front wheel wells are still round, but they are lower and cut more deeply toward center, while the leeward side is cut abruptly downward and capped with a cool-looking LED “blade of light” side turn signal.
Kenworth engineers made some interesting aerodynamic improvements, focusing on the air flow under the truck, where all the knobby stuff like oil pans and drive axles live. They have also developed a swing-out, side-extender fairing extension that succeeds in closing the tractor/trailer gap without limiting drivers’ access to the rear deck and the air and electrical lines.
Also included in the facelift are some new interior colors and accent trim, and just a few new in-cab amenities. It’s the same cab, the same basic dash layout, but the star of the upgrade is a now 15-inch, highly customizable digital A-panel. Judging by the comments I’ve seen online, most seem to like it. The naysayers and fans of a more traditional analog dashboard, however, aren’t keeping their displeasure to themselves.
“Our inspiration for this new model came from race cars, iPhones and the craftsmanship of a fine watch,” noted Kenworth Chief Engineer Joe Adams during the unveiling last week. “This created the atmosphere where we designed the Next Generation T680, that balances the need to be functional and efficient, yet beautiful and sophisticated.”
Let’s break it down bit by bit to see what’s new on the T680 Next Generation.
“We exceeded the superior fuel efficiency of the current T680, through aerodynamic advancements and design innovations,” said Adams. “As a result, Kenworth T680 Next Generation is the most aerodynamic truck in company history. Our design enhancements offer up to 6%* fuel efficiency on a T680 Next Gen equipped with a 76-inch sleeper and EPA 2021 Paccar MX-13 engine over a comparably spec’d T680 with EPA 2017 Paccar MX-13 engine.”
The asterisk (*) is the standard caveat that “individual fuel economy improvement will vary depending on use, road conditions and other factors.” Of course, the 2021 version of the MX-13 engine probably contributes in a significant way to the claimed possible 6% percent gain. Not much was said about the MX-13 during the presentation, so we don’t know how much better it is than the 2017 version referenced in the comparison.
The Next Generation T680 includes a new aerodynamic bumper and hood, turning vanes, durable lower fairing extensions, chassis fairings, wheel well closeouts, 28-inch side extenders, tandem drive axle fairings, and wheel covers to keep the airflow closer to the cab and reduce drag-causing turbulence.
Kenworth changed up the frontal profile significantly, starting with a hood that’s 8 inches narrower at the front than the previous version. That required a redesign of the cooling package, making it taller overall but dropping further down between the frame rails. The narrower hood cuts into the wind more easily, sweeping it off to the sides and over the wheel wells. The fender tops have been lowered and end with a sharp cutoff at the rear that “releases” the air cleanly in front of the steps. Turbulence is the enemy here, so the goals was to get the air flowing more smoothly from the front and out along the sides of the cab and the chassis fairings.
The bumper has an improved profile to direct air past the wheel openings, and a new air-dam design guides and controls airflow under the chassis. It also provides protective coverage under the cooling module while maintaining the same ground clearance as the previous model. The changes to the grille width permitted more generous radii around the edges, which allows air to stay better attached as it goes alongside the hood. The bumper also has more generous radii on the corners, providing similar benefit. The new T680 includes an A-pillar turning vane that directs the slipstream smoothly from the windshield and around the A-pillar. This lessens the wake next to the side windows and will probably help lower in-cab noise levels, too.
Kenworth also developed a unique ducting system within the hood structure to help move air (and heat) trapped under the hood out into the slipstream. It features a passive flap from the underbody to the outerbody behind the fender that opens and closes based on air pressure and wind conditions. The vent outlet is located at the back of the wheel well, surrounding the hood latch.
The undercab chassis fairings have been resculpted and feature a bigger and safer step for improved entrance and egress. There’s also a new attachment system for faster fairing replacement if a repair is needed. There’s now a small flip-open door along the top of the driver-side chassis skirt to facilitate inspection of the battery box without removing the entire panel.
Perhaps most notable is an innovative opening side-fairing extender at the rear of the cab. Optional side-extenders now reach back a full 28 inches, but the final 9 inches swing out to provide access to the rear deck for hooking up the air and electrical lines.
Some chassis packaging improvements now make shorter wheelbases possible, and that can reduce the tractor/trailer gap to somewhere between 38 and 42 inches to further reduce turbulence as air transitions from the side of the truck to the side of the trailer.
“One of the biggest ways you can improve aerodynamics is by decreasing the trailer gap,” says Kenworth Design Director Jonathan Duncan. “Getting that trailer as tight as you can up to the back of the sleeper can make it really difficult for any kind of access up onto the chassis or for even hooking up your trailer lines and everything. This innovation solves both those problems.”
Kenworth says a shorter wheelbase also opens the possibility of using a lighter front axle and lower ply steer tires for additional cost savings.
Interior and Chassis Upgrades
Kenworth went easy on the interior upgrades this time around but is offering a few new amenities and a new color scheme, featuring a classy-looking black dash with woodgrain accents and copper-colored fabric inserts in the seats and door pads. The T680 Next Generation with a Diamond VIT interior option has a rich copper-colored madrona insert in the door pad with black stitching to match the black door. The Diamond VIT sleeper interior has fine black Diamond panels with madrona stitching, which also appears on the leather-wrapped steering wheel.
“What we really wanted to do was bring some more contrast and refinement into the interior,” Duncan said during the presentation. “We have a nice new black color on all the lower bits and then our light tan or light gray up above. And in the premium Diamond VIT interiors, we have a new color called madrona, which is a rich coppery color. That is on the center of our leather seats and in the stitching. We think that really gives it a high-end premium look.”
The T680 Next Gen with 76-inch high-roof sleepers can be spec’d with the optional Kenworth Cargo Shelf – a 5.5-inch storage shelf with multiple secure tiedown points. Two LED lights on the shelf’s underside provide lower bunk lighting, Kenworth says.
Among the less obvious chassis modifications were those needed to accommodate the redesigned radiator. In narrowing the grille, the same radiator surface area had to be maintained, says Chief Engineer Joe Adams.
“We designed it to be a little bit narrower, and we lowered it down in between the frame rails,” he said. “The design includes deer-bar strike protection and all the other goodies that we put there to keep the radiator safe and in its place.”
Like the current T680, Adams said the front-end was designed for easy and relatively inexpensive repair in the event of a minor incident. Parts of the bumper can be replaced in sections rather than replacing the entire bumper, and the front-end bits are still accessible for quick and easy servicing.
Perhaps the most noticeable difference between this and previous versions of the truck are the optional LED headlights with signature daytime-running-lights.
“The dynamic shape of the DRL light follows the curve of the headlight giving a distinctive look while tying into the shaped-by-the-wind fender surfaces,” explained Duncan. “They allow us to have a really expressive look. You’re going to know it’s a Kenworth when it’s coming towards you.”
There’s even a built-in infrared heater to help clear ice and snow before it accumulates on the lens.
Digital Display and SmartWheel
Of all the new features on the Next Gen T680, the one generating the most buzz is the digital instrumentation display. It’s a “glass cockpit” concept offering a high level of customization with nearly 50 display options. The design is intuitive and easily adjustable to enable drivers to match their preferences, while also automatically displaying critical content.
While the factory layout of content is prioritized and intuitive, drivers can create a personalized display for easier access to information and a layout that fits their needs.
Drivers can choose from two “minimized” views showing only the truck speed, tachometer and standard content in the header and footer area for minimal visual distraction and impact on night vision. The basic view option adds digital gauges such as fuel, air, coolant and oil pressure to the on-screen content. In any viewing mode drivers will still be alerted to warnings or faults by having them presented automatically on screen.
Drivers who prefer to view all featured truck information will see additional gauges such as axle temperatures, torque, air filter restriction, brake application pressure and more – as specified on the truck. Current trucks show about 23 gauge functions, but the system can show as many as 38 on-screen, all on the A-panel directly in front of the driver rather than over on the B-panel.
“With this screen-based instrumentation system, drivers can select the level of information detail they want to see, while the technology behind it lets us employ automation to show drivers what they need to see when they need to see it,” said Laura Bloch, Kenworth assistant general manager for sales and marketing.
Drivers can set their own display preferences, but the system cannot store more than one profile. Team drivers will have to adjust the setting to suit their own preferences when they get behind the wheel.
Kenworth says the design team spent countless hours interviewing drivers and observing how they use the current T680 display.
“We learned that drivers want an intuitive display that they can control and gave them the right information at the right time,” said Zack Slayton, leader of Kenworth’s software development team. “We spent over a quarter million hours designing and testing this display and the steering wheel with hundreds of additional drivers across dozens of fleets.”
Drivers can scroll up and down through the display hierarchy using the standard Next Gen SmartWheel, which also puts cruise control and radio functions at the driver’s fingertips.
When the truck is shut off, the screen transitions to a trip summary view, or optionally, it can provide a Driver Performance Assessment report and coaching advice. A Drive Summary, which reports statistics on information such as average fuel economy, idle time, cruise control usage, as well as any potential mechanical issues, also appears at the day’s end.
Responding to reporters’ questions about the replacement cost and the complexity of the digital display, Adams said the replacement cost would be similar to that of the current driver display.
“Digital display technology has grown incredibly robust over the years,” Adams said. “Since there are no mechanical parts — and a data bus instead of individual wires, — this system is considerably more reliable than traditional instrumentation.”
All That and ADAS Too
The T680 Next Gen brings two new driver assistance technologies to the Kenworth lineup, lane-keeping assist and torque-assisted steering, along with a suite of other ADAS functionality.
Torque-assisted steering is designed to reduce driver fatigue by providing additional torque to the steering column. The amount of torque assist is based on vehicle speed, with higher speeds resulting in less assistance and a tighter steering feel. Drivers traveling at low speeds will notice a lighter steering feel and more torque assist. The system adjusts accordingly to varying driving conditions and applies necessary torque to best handle adverse driving conditions such as heavy crosswinds.
The lane-keeping assist option is designed to help drivers stay in their lane. The system uses camera input to identify when the truck is departing the lane and provides a “nudge” to correct the direction of the truck. The feature requires Bendix Fusion and comes with torque-assisted steering.
Other advanced driver assistance technology available on the T680 Next Gen include adaptive cruise control, lane departure warning, collision mitigation, and side object detection:
- Adaptive cruise control is integrated with your standard cruise control, and “reads” traffic conditions via a front-facing radar sensor and modulates the throttle and the brakes to keep the truck at a pre-set distance from the vehicle in front of it. Then, when the slowdowns clear, the system re-accelerates the vehicle back to the set speed.
- Kenworth’s lane-departure warning system helps combat lane drift due to fatigue and distractions. When activated, the system continually monitors the truck’s location related to lane markings and automatically emits a distinctive audible warning whenever an unintended lane change (unsignaled) is detected – alerting the driver to make a correction.
- The Kenworth collision mitigation system detects when the truck may be about to collide with another vehicle or object, alerts and assists the driver by taking pre-emptive braking action – when necessary – helping the driver potentially avoid or reduce the severity of a collision.
- Kenworth’s side object detection system continuously monitors the passenger side of the truck and provides the driver with audible and visual alerts when an object or vehicle has entered certain zones.
Also standard the truck is Kenworth TruckTech+ Remote Diagnostics. The system enhances vehicle diagnostics by providing engine health information to fleet managers and Kenworth dealers. The system diagnoses the issue and provides the recommended solution to the driver and fleet manager.
The Kenworth T680 Next Generation is available as a day cab and 40-inch, 52-inch and 76-inch-sleeper configurations.
The standard powertrain is the EPA 2021 Paccar MX-13 engine (405-510 HP/1,550-1,850 lb-ft) with remote diagnostics and over-the-air updates, Paccar 12-speed automated transmission and Paccar 40K tandem drive axles. Optional engines include the MX-11 engine (355-455 HP/1,250-1,700 lb-ft), and remote diagnostics.
While none of the press material mentioned Cummins or Eaton, during the Q&A after the reveal, Chief Engineer Joe Adams said Kenworth has the same offering of transmissions that they have in the current T680.
Hood options will vary with the engine spec. The 125-inch BBC is the standard spec with the MX-13 engine and a 119-inch BBC hood is offered with the MX-11 engine.
The T680 Next Generation is expected to ramp up production in the second quarter of this year. Customers will be able to order either the current or the new version concurrently until at least the end of the year. The phase-out of the previous T680 will depend on customer demand, Kenworth officials told reporters in a press conference call following the unveil.