It's been 15 years since Toyota brought the T100 (its first so-called "1-ton" truck) to the U.S. with just 150 hp under the hood. Since then, the truck evolved into the Tundra, which was considered by many to be a 9/10-ths scale model of a fullsize American pickup. Then, after years of testing our domestic market and taking over the compact truck segment with the Tacoma, the world's richest automaker decided to make the Tundra fullsize for 2007-and gave it dual rear wheels and an 8.0L Hino inline-six turbodiesel engine for the SEMA show.
The 260 hp and 585 lb-ft ratings...
The 260 hp and 585 lb-ft ratings may seem low, but those numbers are for 35,000-pound GVW trucks.
Toyota Diesel Power
The massive 488-cubic-inch Hino J08E-TB turbodiesel in this Tundra is no Cummins, Duramax, or Power Stroke. It was designed for delivery trucks that haul with a GVWR of 35,000 pounds, and has a power rating of 260 hp and 585 lb-ft of torque without any modifications, which would be more than enough grunt to move the Tundra chassis along with a 20,000-pound trailer. Just like the engines in modern 1-ton diesels, the J08E-TB uses common-rail fueling, a variable-geometry turbo, an electronically controlled intake throttle, and twin EGR coolers to lower NOX emissions. Unlike the stock engines in the delivery truck applications, this one gets to breathe through a free-flowing 4.5-inch Magnaflow exhaust that reduces EGT while towing, and sweetens the sound whenever the Hino is fired up.
5-Speed and HD Axles
To deal with the torque of the large displacement diesel, the Toyota Motorsports Technical Group drastically modified the drivetrain. A heavy-duty Eaton 5-speed manual is used to transmit the massive amounts of torque from the engine back to a Meritor axle that uses "Hypoid-Generiod" gearing for strength and quiet operation, plus it can be equipped with a remote-actuated locking differential.