Running on standard 91 RON fuel, the new 2.5-litre engine uses a claimed combined-cycle 8.4 litres per 100km in front-wheel drive form or 8.8L/100km as an AWD, down from 11.0-11.2 on the old 3.7-litre V6.
The savings on the urban cycle are higher still, with fuel use cut by between 25 and 27.6 per cent.
The combined-cycle figure also undercuts petrol seven-seater rivals such as the top-selling Toyota Kluger V6 (10.2-10.6), though most seven-seater diesels are more frugal still.
However, the better economy comes at the expense of less power. The new 2.5 makes 170kW, down from 204kW with the old 3.7. Torque is up though, from 367Nm to a potent 420Nm at 2000rpm.
As you may recall from our US drive, that market’s new 2.5 CX-9 has 186kW/420Nm. We’ve asked Mazda Australia why there’s a difference, but expect it to be down to fuel grades and, potentially, hot-weather grading. Mazda Australia has always cited a 169kW-170kW figure, so this isn't a revelation.
Update: Mazda Australia has confirmed it cites the lower output of 170kW because this is the cited figure using 91 RON fuel.
The new engine runs a high 10.5:1 compression ratio. It also includes a dual-valve Dynamic Pressure Turbo that generates power more quickly and a cooled exhaust gas recirculation system that lowers engine temperatures without having to add extra fuel.
“The fuel economy numbers alone position Brand-New Mazda CX-9 as a class-leading option for buyers wanting a large, seven-seater, petrol SUV,” said Mazda Australia marketing director Alastair Doak.
“The all-new SKYACTIV-G 2.5T turbo charged engine is an impressive piece of Mazda innovation with world-first technology that prevents turbo lag. The result of this, in part, is in the low fuel economy numbers.
“The CX-9 has always been very highly regarded; we think that even more SUV buyers will want to acquaint themselves with this car once they see the brand-new new model in the metal. There’s a lot to like in this vehicle.”