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Drivers will appreciate Toyota’s civilized beast of a powertrain

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Remember when hybrids were strange little cars with low fuel consumption?

We neither. That was a long time ago.

Hybrid powertrains that aren’t plug-ins can be found in the leanest, fastest sports cars in the world, from Porsche and Lexus models to Ferrari supercars, alongside a host of affordable mainstream vehicles.

But powering pickup trucks that can carry heavy loads all day long promises to be an important new task for hybrids.

Mild-hybrid pickups with 48V architectures are already well established, but full hybrids with truly outrageous torque numbers are now becoming a thing. Ford wowed us last year with its F-150 hybrid, which won the top 10 engines and propulsion systems in 2021. This year’s Toyota Tundra 3.5L Twin-Turbo V-6 i-FORCE MAX hybrid receives a Wards 10 Best Engines & Propulsion Systems trophy.

The massive 583 lb.-ft. (790 Nm) of torque and 437 hp stand out, but also excellent NVH characteristics impressed the Wards judges. And while it doesn’t list diesel-level fuel economy figures, the rating is fair for a pickup that can tow up to 12,000 lbs. (5,443 kg).

Toyota has created an incredibly civilized beast of a powertrain that drivers will appreciate as soon as they put their foot on the accelerator.

The 3.5 L Twin-Turbo V-6 has only the power of a V-8 and has a deep, rumbling exhaust note when driving around town. In addition to adding a boatload of torque at low speeds, the electric motor provides smooth power delivery to the wheels to the point where the tundra feels more like a locomotive than a truck. Whether you’re running errands or pulling a huge trailer, this drivetrain delivers a smooth ride.

“The switch between electric and gas is imperceptible,” said Judge Christie Schweinsberg. “A far cry from the old days of hybrids.”

The large NVH is no coincidence. All judges mentioned the seamless nature of the hybrid setup’s power delivery. Toyota executives say this has been a key objective from the start. Engineers wanted constant pulling power in all driving situations, leading them to adopt a single-engine parallel-hybrid configuration that allows the combustion engine and electric motor to operate independently or in combination. It’s not a new concept, but it’s the first time Toyota has offered the system, which is also the sole powertrain in the ’23 Sequoia SUV.

The compact setup uses a permanent magnet motor sandwiched between the longitudinal V-6 and 10-speed automatic transmission, which sends power to all four wheels via a transfer case after the gearbox.

The single-engine setup isn’t as efficient as a twin-engine drive, but in this case, the engineers have subordinated fuel economy to the primary goal of continuous torque, as required in a full-size truck application used for hauling heavy loads or pulling large followers. The system also smoothes shifting and transitions between hybrid modes and reduces the amount of downshifts compared to the non-hybrid powertrain.

Backed by a 1.87 kWh nickel-metal hydride battery, the 650 V Aisin-powered motor generator adds 36 kW (48 hp) and 184 lb.-ft. (249 Nm) of torque to the power of the 3.5 liter twin turbo V-6, for a total of 437 hp and 583 lb.-ft. Unlike many gas-electric hybrid systems, Toyota says the electric motor’s instant-on, zero-rpm torque is additive, rather than compensating for the reduction in ICE output. The system is also capable of electric-only driving at low speed up to 29 km/h.

“Toyota’s goal of emphasizing constant traction rather than maximum fuel economy has been achieved. They have done an impressive job of creating a seamless ICE-EV setup in a truck,” summarizes judge Bob Gritzinger.

Drew Winter

Toyota engineers explain details of Tundra i-FORCE Max to Ward’s 10 Best judges at the company’s Tech Center in Saline, MI.