Australian new-car buyers can’t trust the official fuel consumption figures for the vast majority of models now tested in the real world by the Australian Automobile Association (AAA).
Following its latest round of federal government-funded testing, Australia’s peak motoring body has now compared the actual fuel consumption and emissions of 141 new petrol, diesel and hybrid models against the official claims displayed on the window stickers of new vehicles in showrooms.
The latest results, published at realworld.org.au, show about 80 per cent of models tested couldn’t match their window-label number, with variations of up to 25 per cent.
The petrol GWM Tank 300 off-road SUV was the furthest away from its official claim, with its 11.9L/100km test result 25 per cent above its official combined fuel consumption figure of 9.5L/100km.
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Previous testing has shown even bigger variations of up to 35 per cent above official fuel consumption figures.
Diesel-powered models in the latest tests included the Kia Tasman ute – the Korean brand’s first rival for the Ford Ranger and Toyota HiLux.
The Tasman used four per cent more fuel in its real-world test, at 8.4L/100km against its official figure of 8.1L/100km.
The BYD Seal and BMW iX1 were the only electric vehicles (EVs) in the latest round of testing. Both fell well short of their claimed range on a single battery charge, with the iX1 found to fall 10 per cent short and the Seal 25 per cent off.
A total of 11 EVs have been tested so far, with results ranging from 3.0 per cent better than claimed to as much as 31 per cent worse than the official claimed range.
Somewhat ironically, the Ford Mustang GT – which runs a 5.0-litre V8 petrol engine – used 22 per cent less fuel than its official sticker number in real-world testing.
Across all models tested so far, the AAA found 76 per cent used more fuel and produced more emissions than their windscreen stickers state.
“The AAA supports the introduction of increasingly stringent vehicle emissions regulation, but we also want to make sure our car fleet is getting cleaner in the real-world, not just in the lab,” AAA managing director Michael Bradley said in a statement.
The latest results follow the first report on the federal government’s New Vehicle Efficiency Standard (NVES), which revealed the auto brands that exceeded their emissions targets in 2025.
“By independently measuring fuel use and emissions performance in real-world conditions, this program provides transparency about NVES-related emissions reductions, and the degree to which they are being realised on Australian roads,” Mr Bradley said.
Meantime, transport sector emissions in the 12 months to September 2025 fell 0.4 per cent as part of a 3.1 per cent fall in Australia’s total emissions during that period.
Despite this, transport sector emissions were still 23 per cent higher than they were in 2005.
Below are the fuel consumption results from the latest round of the AAA’s real-world testing.
| Vehicle | Fuel type | Mandated lab test claim (L/100km) | AAA testing result (L/100km) | Disparity |
|---|---|---|---|---|
| 2026 Toyota Yaris hybrid | Petrol | 3.3 | 3.6 | +10% |
| 2026 Mercedes-Benz C300 | Petrol | 7.1 | 7.3 | +3% |
| 2026 Hyundai Kona | Petrol | 6.6 | 6.9 | +5% |
| 2026 Honda HR-V | Petrol | 6.2 | 7.4 | +19% |
| 2026 GWM Tank 300 | Petrol | 9.5 | 11.9 | +25% |
| 2026 Ford Mustang EcoBoost | Petrol | 9.4 | 8.8 | -6% |
| 2026 Ford Mustang GT | Petrol | 13.6 | 10.7 | -22% |
| 2026 Mercedes-Benz GLE450d | Diesel | 7.4 | 6.6 | -11% |
| 2026 Kia Tasman | Diesel | 8.1 | 8.4 | +4% |
| 2026 BYD Seal | EV | 650km | 488km | -25% |
| 2026 BMW iX1 | EV | 400km | 360km | -10% |
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