The future of Isuzu: 2025 Isuzu D-Max and MU-X debuts with new smaller 2.2-litre engine in Thailand as it moves away from 3.0-litre engine amidst tough new emissions laws

Isuzu has debuted its updated range of D-Max utes and MU-X SUVs with a new 2.2-litre turbo-diesel engine which could potentially replace, or at least add to the brand’s range of engines offered in Australia as the new vehicle efficiency laws begin to bite.

Now fully detailed and on sale in Thailand, the 2.2-litre Ddi ‘Maxforce’ engine produces 122kW/400Nm and sits between the 1.9-litre ‘RZ4E’ four-cylinder engine (110kW/350Nm) and 3.0-litre ‘4JJ3’ engine (140kW/450Nm) in the brand’s international line-up.

This new engine is mated to a new eight-speed torque converter automatic transmission replacing the six-speed automatic currently paired with the 1.9-litre and 3.0-litre engines.

Isuzu’s Thai division showed a range of vehicles equipped with the new ‘Maxforce’ engine ranging from lifted 4x4 versions of the MU-X to low-riding work-focused two-wheel-drive single or space-cab versions of the D-Max at the Bangkok Motor Show.

Isuzu has already launched a mild-hybrid version of the 1.9-litre four-cylinder diesel engine in Thailand which adds a small battery and 48-volt starter motor capable of assisting with regenerative braking. It maintains the same overall power output as the existing 1.9-litre engine (110kW/350Nm).

Both of which seek to reduce the emissions and fuel consumption of Isuzu’s range, as the automaker stares down the barrel of emissions laws not only in Australia, but now even in South East Asian countries where the bulk of the brand’s sales take place.

For example in Thailand, where Isuzu manufactures the D-Max and MU-X, the government is about to introduce emissions laws equivalent to Euro 6, which for diesel engines kicks off in 2026. This will mean Isuzu’s Euro 5-standard engines will no longer be able to make up the majority of its sales without avoiding fines.

In Australia, both of Isuzu’s current engines pass the first round of NVES, but the fan-favourite 3.0-litre engine will be in trouble in 2026 and beyond. The brand will be able to continue selling the engine, but will attract fines if it makes the bulk of sales as it does presently.

As a result, the brand may be forced to bring in the 2.2-litre diesel engine and 1.9-litre MHEV, as Toyota has done with its 48-volt HiLux range.

Isuzu is one of the automakers most exposed to Australia’s new emissions regime, which necessitates hybrid, plug-in hybrid, and fully electric vehicles to be a significant part of sales to balance out higher-emitting engines.

The Japanese stalwart has shown an upcoming fully electric D-Max, although the brand recently promised it would be a part of its new model strategy potentially within the next two years.

Of the new 2.2-litre diesel engine, an Isuzu spokesperson told CarsGuide in November 2024 the brand was “monitoring reception” to news of the new engine, but would have to “ensure any product updates to our local range meet the unique requirements of our market before introducing any change locally".

To that end, the brand pointed out the version of the 3.0-litre engine sold in Australia is unique to Australian specifications with some upgraded hardware to better suit our conditions.

Down-sized diesel engines may begin to become more important as brands with 4x4-heavy line-ups seek to reduce their emissions impact.

Kia’s incoming new Tasman ute, for example, will also use a 2.2-litre diesel powerplant, while Mitsubishi chose to continue with its relatively lean 2.4-litre engine for its new Triton, despite pressure from brands like Ford, which went in the opposite direction introducing a new 3.0-litre V6 when the current-generation Ranger launched.

Either way, in recent comments to CarsGuide Isuzu's representatives said the brand was determined to find a way to survive in our market.