Tata Sierra EV QWD: What Makes it Different From Traditional AWDs?

Tata Motors is all set to launch the Sierra EV on June 30, reviving the rugged, go-anywhere ability into the Sierra name, now with modern electric power. Its all-wheel drive system, which Tata calls ‘QWD’, promises strong performance across different driving conditions. 

As we close in on the Sierra EV's official launch, here's a detailed look at what QWD exactly is, how it works, and how it differs from AWD systems in ICE and other EV cars.

What is Tata's QWD System?

QWD stands for Quad Wheel Drive, Tata's name for its dual-motor all-wheel-drive setup in electric vehicles. It builds on the company's experience with platforms shared in the Harrier EV and draws from the capable engineering heritage linked to Land Rover DNA. 

In simple terms, QWD uses two electric motors, one each at the front and rear, to send power to all four wheels independently. This gives better traction and control compared to single-motor setups. 

Tata will offer the Sierra EV with both RWD and QWD options, with the latter being suitable for those who often drive on highways, hills, or light off-road trails.

Also Read - New Tata Sierra EV Teaser Shows Full Front View And Interior Glimpse
 

How is QWD Different From Standard AWD?

Traditional all-wheel-drive systems in petrol or diesel cars rely on mechanical parts like transfer cases, differentials, and driveshafts to distribute power from a single engine to all wheels. These systems add weight, can lose energy through friction, and are less flexible in instantly adjusting power between axles. In tough conditions, drivers sometimes need to manually lock differentials or select modes, and there is always some lag.

In contrast, EV AWD systems use two similar motors, often permanent magnet types, which work well for quick acceleration but may not always optimise for varied Indian terrains like loose sand, mud, or snow. Tata's QWD addresses this limitation by pairing different motor types for better overall capability.

The rear motor is a powerful Permanent Magnet Synchronous Motor (PMSM), delivering strong torque, high efficiency, and smooth performance for everyday driving and highway runs. In the Harrier EV QWD, this rear motor produces around 235 bhp. It handles most daily driving conditions, helping with better range and responsive power.

The front motor is an induction motor, making about 155 bhp. Induction motors are simpler, more durable, cheaper to produce (no rare-earth magnets needed), and handle heat better during demanding use. They engage mainly when extra traction is required, such as during strong acceleration, on slippery surfaces, or off-road situations, and can freewheel when not needed to avoid drag and save energy. 

Together, they provide a combined torque output of 504 Nm and quick 0-100 km/h times (around 6.3 seconds in boost mode). Drivers get multiple terrain modes such as Normal, Rock, Mud, Sand, Snow that adjust power delivery, throttle response, and other parameters automatically. Features like off-road assist, transparent underbody view, and boost mode further enhance control.

All this advanced tech makes Tata's QWD more capable for multiple terrains than standard AWDs. 

Also Read - Best Rugged 4x4 and AWD SUVs You Can Buy
 

Tata Sierra EV Battery Options and Range

The Sierra EV is expected to use the same 75 kWh battery pack option as the Harrier EV for its higher variants, alongside a smaller 65 kWh pack. 

The Harrier EV delivers a real world range of 380-425 km with the 65 kWh battery, and 430-500 km on the 75 kWh unit. Expect figures for the Sierra to be higher for the respective battery packs, thanks to its lighter weight.

The QWD system will likely be paired exclusively with the larger battery for optimal performance. The same battery packs are also expected in the upcoming Safari EV.

Fast charging and good real-world range should make it practical for long trips, while the acti.ev+ platform underneath supports solid build quality and features.

Tata Sierra EV Rivals

The Sierra EV will enter an evolving, but competitive space, going up against the Mahindra BE 6, MG ZS EV, Hyundai Creta Electric, and the Maruti Suzuki e Vitara.

Right now, Tata holds the first-mover advantage, being the only carmaker offering an AWD system in the mass-market mid-size electric SUV segment in India. 

All its aforementioned rivals stick to front-wheel-drive or rear-wheel-drive configurations, which although are simpler and lighter, but can struggle in tricky conditions. 

Image Credits: Tata Motors