Subaru intends to stop making its original e-Boxer mild-hybrid powertrain, now found in the Australian-market Crosstrek small SUV, as it leans more heavily on hybrid technology from Toyota.

Following over ten years of work, the company informed Nikkei it will halt the mild-hybrid e-Boxer setup, which it started developing in 2013 and launched in Japan with the 2018 Forester SUV.

In view of advances in electrification and tougher environmental rules, Subaru reviewed its lineup and chose to end the mild hybrid vehicle effort, according to a statement reported by Nikkei.

The e-Boxer mild-hybrid powertrain reached Australia in March 2020 with the launch of the Forester Hybrid e-Boxer and XV Hybrid e-Boxer models.

Both featured a 110kW/196Nm 2.0-litre horizontally opposed boxer four-cylinder petrol engine, a continuously variable transmission, and a 12.3kW/66Nm electric motor with a lithium-ion battery.

At introduction, Subaru Australia stated the e-Boxer regenerative braking and three drive modes cut urban fuel use by as much as 14 per cent in the XV Hybrid and 19 per cent in the Forester Hybrid versus their petrol versions.

The setup could also propel the vehicle on electric power alone up to 40km/h. It stays on sale locally in the XV successor, the Crosstrek, though Subaru has not specified the timing of final Australian deliveries.

The brand posted the third-highest emissions liability among automakers in the first period under Australia's New Vehicle Efficiency Standard, which gradually lowers fleet-average tailpipe emissions limits.

Instead of the mild-hybrid system, Subaru will keep offering its newer strong hybrid powertrains and battery-electric vehicles, drawing more on Toyota technology.

The two companies have collaborated for years on vehicles such as both generations of the Toyota GR86, previously the 86, and the Subaru BRZ sports coupe.

In 2025 the sixth-generation Forester reached Australia with Subaru's next-generation e-Boxer strong-hybrid system, pairing a 2.5-litre four-cylinder boxer petrol engine with a 90kW electric motor and a Toyota-sourced 1.1kWh battery for 145kW total output.

The updated powertrain lowered the Forester Hybrid official combined fuel consumption to 6.2L/100km across all three hybrid grades, a 0.5L/100km gain over the prior version.

Subaru also stopped work on its own plug-in hybrid technology in 2023 and confirmed it would source future systems from Toyota instead.

The partnership has grown to include electric vehicles. The Toyota bZ4X and Subaru Solterra, both produced by Toyota, arrived in Australia in 2024.

The related Toyota bZ4X Touring and Subaru Trailseeker pair followed this year.

Subaru's Uncharted electric SUV, introduced locally in April, shares its platform with the Toyota C-HR EV, expected in Australia in the first half of 2027.