The Isuzu D-Max ute and MU-X large SUV are set to have their flagship engines downsized, but that may not come at the expense of power and torque.
A teaser video posted on social media by Isuzu Thailand – which produces the D-Max, MU-X and Mazda BT-50 for global markets – previews the new MAXFORCE engine that is set to replace the venerable ‘4J’ 3.0-litre turbo-diesel currently powering the models.
Isuzu is yet to detail the new engine, however, Top Gear Philippines reports it’ll be a 2.2-litre unit, based on the newer 1.9-litre four-cylinder ‘RZ4E’ turbo-diesel found in lower-spec versions of the D-Max, MU-X and BT-50 in Australia and abroad.
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“While it is exciting to see that Isuzu continues to innovate with new powertrains, we currently are not in a position to comment on future product plans,” an Isuzu Ute Australia spokesperson told CarExpert.
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“While the 2.2-litre is expected to be a step in the right direction towards meeting lower emissions targets, at this point in time, details of the new powertrain are yet to be confirmed.”
“That said, Isuzu Ute Australia [is] committed to working towards providing a choice of vehicles that are not only compliant with all local legislation, but are fit for purpose and meet the needs of Australians.”
Despite the rumoured 2.2-litre engine’s reduced capacity, it’ll reportedly be as powerful – if not even more so – than the larger 3.0-litre it’s replacing, likely due to a more efficient turbocharger.
It’s possible the upcoming 2.2-litre engine could also deliver some of the fuel savings of the newer RZ4E while not losing any of the 4J’s performance capabilities.
The 1.9-litre engine – added to the Australian lineup in 2021 – offers buyers a cheaper point of entry to the model range, however, its 110kW and 350Nm outputs are down on the 140kW/450Nm figures of the 3.0-litre four-cylinder, which remains a more popular choice for those who are towing and touring.
In Australia, both engines are Euro 5-compliant, however, a Euro 6 version of the 1.9-litre is available in other overseas markets – though Thailand isn’t one of them.
Thai-market versions of the D-Max and MU-X are sold to Euro 4 standards, and lack certain features – such as diesel particulate filters (DPFs) – which are fitted to Australian examples that bring local models up to Euro 5.
The timing of the new engine’s debut overseas comes just a few months before Australia’s New Vehicle Efficiency Standard (NVES) emissions regulations come into effect.
From January 1, 2025, carmakers will have fleet CO2 targets to meet, and they’ll be punished financially from July 1, 2025 if they can’t reach the mandates.
In the case of the D-Max and MU-X, their 1.9-litre engine is more economical and emits less CO2 than the 3.0-litre.
Comparing D-Max SX 4×4 automatic variants of the two engines, the 1.9-litre consumes a claimed 6.9L/100km and emits 180g/km of CO2 on the combined lab cycle. Meanwhile, the 3.0-litre drinks a claimed 8.0L/100km and emits 207g/km.
In 2025, the emissions target for ‘Type 2’ light commercial vehicles – which the D-Max, BT-50 and even MU-X fall under – will be 210g/km, which falls to 180g/km in 2026, 150g/km in 2027, 122g/km in 2028 and 110g/km in 2029.
While Isuzu has typically been slow to introduce new engines in its Australian lineup, the impending NVES regulations could force its hand to fast-track the 2.2-litre turbo-diesel to the local lineup.
Isuzu Ute Australia told CarExpert in April, shortly after the NVES regulations were announced, that it wouldn’t be impossible to meet the emissions targets.
“This is important for us to get it right and the industry to get it right,” said Isuzu Ute Australia PR manager Mark Harman.
“So we want to make sure that the technologies are there and the infrastructures are there. Isuzu Japan has been on the record saying that they’ll introduce that BEV concept… when the infrastructure is ready in other markets after Norway, which is destined for 2025.”
The potential move to a larger RZ4E-based engine as a flagship powertrain offering would reflect Isuzu’s investment in the turbo-diesel powerplant, which debuted in 2017 – making it significantly younger than the 4J which, at its core, dates back to the mid-1980s.
Last month, Isuzu confirmed it would produce the D-Max Hi-Lander MHEV (mild-hybrid electric vehicle), which features a 48-volt system on the 1.9-litre engine.
This fuel-saving technology won’t be available on the 3.0-litre engine, which has been upgraded throughout its life to include direct injection and a variable-geometry turbocharger, but is likely towards the end of its lifecycle.
It’s not yet locked in for Australia but will go on sale in Thailand, only on rear-wheel drive variants and at a 10,000 Baht (circa $450) premium.
Isuzu has previously confirmed it’ll launch an electric D-Max in Australia, but only after it first goes on sale in Norway.
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