A new cab-over-engine (COE) Class 5 work truck from Hino will be shipped to select markets across the U.S. by the fall, and one of the engine options for the Toyota-owned truck will be a newly refined turbo-diesel electric-hybrid powertrain that could have major implications for the powertrain options offered on the Toyota Tundra.
We first saw the system highlighted at this year's in Long Beach, Calif. The Hino 195h uses a 5.0-liter four-cylinder turbo-diesel (and intercooled) engine, electric motor/generator, a six-speed Aisin transmission, a massive nickel-metal hydride battery and a selective catalytic reduction system with a 4.7-gallon diesel exhaust fluid tank. (If you'd like to see a video of how the system works, click here, and scroll to the bottom of the page.)
As you might imagine, this system is pretty heavy, altogether weighing about 2,000 pounds. However, given that the Hino 195h has a gross vehicle weight rating of 19,500 pounds and is likely to run multiple short-distance loaded and unloaded duty cycles, the extra weight isn't much of a drawback for a Class 5 vehicle. Unfortunately, if some reports are correct, those weight numbers would need to be seriously scaled down if this system were to make it into a full-size Tundra.
Rated at 210 horsepower and 440 pounds-feet of torque, the small turbo-diesel could be made to work quite well in a Tundra, hybrid or not, as long as the inverter and battery pack can be modified to be smaller and lighter than the current model. Also, we were told there may be some issues in making this system work with a four-wheel-drive or all-wheel-drive transfer case, as the driveline is already bulky and heavy. Since the system has a start/stop interface clutch between the engine and motor, adding a transfer case into the driveline could be problematic, not to mention space is tight to get a prop shaft to send power to the front axle.
Given the timing of these Hino trucks and the engineering we suspect is necessary to make a modified version work in the Tundra (could something be modified for the Tacoma?), we suspect we'll see something for the 2015-16 model year, but we don't have any confirmation of that. Regardless, this technology looks well done (our only modification would be to add some kind of 110v power outlet generation for various camping or work tool usage), and we're hoping to get some time in one of these trucks as soon as we can. Stay tuned for driving impressions of the Hino cab-over-engine later this year.