The 5.7 is the first truck engine Toyota has built in the U.S., and it’s coming from the Toyota-owned Bodine aluminum plant in Troy, Missouri, and being assembled at Toyota’s manufacturing assembly in Huntsville, Alabama.
If we’re throwing around a lot of U.S. locations, it’s because the Tundra has what Toyota likes to call All-American roots. It was designed and engineered by Calty in Newport Beach, California, as well as Ann Arbor, Michigan. Engine production is in two locations as well: Troy, Missouri, and Jackson, Tennessee, while the vehicles are being built in Princeton, Indiana, and Toyota’s newest truck facility smack in the heart of truck territory in San Antonio, Texas. Toyota understood that to be taken seriously as a truck by American workers, it had to be designed, engineered, and built in the U.S. Lest you think this wasn’t a big deal, it took a fair amount of effort to convince the Japanese heads of Toyota to relinquish control to Toyota Motor Sales in the states. Will it make a difference to customers that Toyota has taken this step? Does anyone care that Toyota employs over 32,000 people in the country or has helped create almost 400,000 jobs here? Maybe; maybe not.
Enough of the flag waving and back to the drivetrain. Any Tundra engine below a 5.7 will receive a 5-speed automatic transmission with a sequential shift, while the 5.7, on CrewMax or Double Cab comes standard with a six-speed electronically controlled automatic transmission with Select Shift. It offers the widest overall gear range of any full-size pickup, reducing the need to have so many different rear-axle ratios like the competitive trucks. The standard final-drive ratio is 3.91:1, while the tow package offers a 4:10. With the tow package comes a tow/haul feature on the 5.7 with the six-speed that holds the gears when going downhill to increase braking control, and stops gear hunting when pulling uphill. The shift lever actually shifts depending on the seating. If you go with a bench seat, the lever is on a column stalk; if you get the bucket seats, the shifter moves to the center console along with a huge flat top storage box that doubles as a work space. That storage box is big enough to fit full-size folders so the trucker actually can use the vehicle as a mobile office.
To make sure the Tundra can handle all the power it’s putting down, Toyota designed two new rear differentials, both as well assembled in America at the new Toyota-owned Hino Motors plant in Marion, Arkansas. Tundras with both the V6 and 4.7 V8 will get a new 9.5-inch ring gear, while the 5.7-liter-equipped trucks get a 10.5-inch ring gear, the largest in the half-ton segment and, Toyota claims, bigger than most ¾-ton trucks. Gearing here is a 4.1:1, and 4.3 with the tow package. The point is that the overall ratio range with the six-speed tranny is as wide as the 4-speeds on both Ford and Chevrolet with their full ranges of final-drive options. Even the front diff is new, with an 8.7-inch ring gear, all-aluminum case, and an automatic disconnecting feature.
Boosting the rear diff also meant changing the driveshaft, and there are even two versions of that. The Regular Cab with the standard bed gets an all-aluminum one-piece shaft, while the Regular Cab long bed and all Double Cab and CrewMax models receive a two-piece shaft with a steel front end and aluminum rear section. The center bearing is supported by a frame crossmember. The object with the two-piece design was to add strength but reduce weight. The aluminum half is 30 percent lighter than steel, which reduces rotational mass and curb weight, as well as unsprung weight. Toyota also notes that it helps reduce NVH throughout the cabin as well.
Reducing NVH is a big deal to Toyota, and a big part of that—and possibly the most controversial part of the new Tundra—is the frame. While many of us expected Toyota to build the new Tundra with a fully boxed frame, it didn’t do that. Toyota created something called a Triple Tech frame, which incorporates three unique sections. The front third is boxed for strength to carry the engine and provide frontal crash protection. The middle, where the cabin sits, is a rolled C-channel with top and bottom flanged reinforcements for strength but also to provide better ride comfort. The rear section is an open C-channel for maximum bending resistance and strength to carry heavy loads.