Stellantis Preps New 48-Volt Mild-Hybrid Powertrain For South America

Stellantis is getting ready to roll out a new wave of mild-hybrid (mHEV) models across South America in the coming year. According to information uncovered by our friend Marlos Vey Nidal at Autos Segredos, this electrified setup is expected to be applied to popular nameplates such as the Fiat Toro, Jeep® Commander, and Jeep Renegade. While the details are still emerging, we’re beginning to see a clearer picture of what this system will look like and how it will perform in real-world driving.

The Basics Of The 48-Volt Setup –

At the heart of Stellantis’ new 48-volt mHEV powertrain is the familiar turbocharged 1.3-liter FIREFLY I4. North American drivers may recognize this engine from the 2023 Jeep Renegade, though in South America, it’s tuned for flex-fuel use and called the Turbo 270 Flex, allowing it to run on gasoline or ethanol.

Backing up the turbocharged I4 is a small electric motor rated at 28 horsepower (21 kW) and 5.6 kgfm (about 40 lb.-ft.) of torque. While that doesn’t sound like much on its own, the electric assist helps in two big ways: it improves low-end responsiveness when accelerating, and it can reduce fuel consumption by letting the gas engine work less in certain conditions.

A compact 0.9 kWh 48-volt battery mounted under the driver’s seat stores the energy. This pack is charged through regenerative braking and supported by the system’s dual motors. The electronic management software automatically decides when to run in full gas, electric-assist, or hybrid mode, all with the goal of improving efficiency without changing the way these vehicles drive.

Why Stellantis Isn’t Using A Dual-Clutch Transmission – 

One of the more surprising revelations is Stellantis’ decision to stick with the 6-speed AT6 Aisin torque-converter automatic instead of switching to a dual-clutch (DCT) setup. On paper, DCTs are lighter and more efficient at delivering power because they don’t rely on a torque converter. That means less power loss and a quicker response, which could make better use of the electric motor’s boost.

However, Stellantis seems to be favoring durability and simplicity here. Aisin’s AT6 is already well-proven in these markets, easier to service, and less costly to produce. That could play a big role in customer satisfaction and long-term reliability. The trade-off is that the electric motor’s extra punch won’t always feel as immediate as it would in a DCT-equipped car.

What To Expect On The Road – 

So what does all of this mean for drivers? In practice, the 48-volt system will give vehicles like the Jeep Commander and Fiat Toro extra torque when pulling away from a stoplight or passing on the highway. The mild-hybrid system also allows for smoother stop/start operation, less engine strain in city driving, and improved fuel economy—especially important in markets where fuel prices remain volatile.

While Stellantis hasn’t released official performance or efficiency numbers yet, the T270 Hybrid badge expected for these models hints at a balance of usable power and economy. The company is essentially taking the proven architecture of its 12-volt mild-hybrid systems found in the Fiat Pulse and Fastback, then doubling down with more voltage and more capability.

Looking Ahead – 

With South American customers soon gaining access to this new mHEV option, Stellantis is showing how hybrid technology can be adapted for regional needs. Instead of going straight to plug-in hybrids or full EVs, the brand is rolling out practical steps that improve efficiency while maintaining affordability and compatibility with local fuel options. For markets like Brazil, where flex-fuel capability is vital, this 48-volt system could be the sweet spot between old-school gasoline power and the electrified future.

Source: Autos Segredos