The Australian Automobile Association (AAA) has just completed the third round of its ongoing Real-World Testing Program (RWTP).

Eight out of 21 cars tested in the latest round, covering a mix of SUVs, passenger cars and utes, recorded fuel consumption levels between 6% and 31% higher than in their laboratory test results.

The Suzuki Swift returned the highest deviation of 31% with a real-world fuel-consumption figure of 6.3L/100km, compared to its 4.8L/100km lab test result.

The AAA said the discrepancy between the Swift’s lab result and its real-world result was significantly higher than the previous highest deviation of 16-18%.

The Japanese hatchback also recorded on-road carbon monoxide emissions more than double the regulated lab test limit.

The Subaru Forester Hybrid was another vehicle to use significantly more fuel in real-world testing than it achieved in laboratory tests.

Despite being a hybrid, the Forester’s 7.4L/100km was 10% higher than its mandated lab result (6.7L/100km) and only slightly better than the 7.7L/100km real-world results of its larger and more powerful stablemate, the Outback.

Eleven other vehicles delivered fuel consumption within 5% of lab test results, while eight exceeded their lab test fuel consumption by 6% or more, and two vehicles had on-road fuel consumption 10% to 13% lower than their lab results.

RACQ Principal Technical Researcher Andrew Kirk said that even though some vehicles accurately depicted their fuel consumption on the windscreen label and a few even used less fuel, the majority tested so far have used more fuel than indicated on the label.

“Buying a new car is a huge investment and motorists deserve to know how their vehicle is likely to perform in Australian conditions,” Mr Kirk said.

“If a car you’re interested in will use more fuel in the real-world compared to its reported lab results, that has a direct impact on your hip pocket at a time when many Australians are watching their every dollar.”

In addition to the Swift, the on-road emissions of five other vehicles exceeded current or future Australian regulatory lab limits for tailpipe emissions.

AAA Managing Director Michael Bradley said the testing program was delivering surprising results.

“In our latest batch of results, there is a 44% spread in the gap between the tested cars’ fuel consumption lab results and their on-road performance,” Mr Bradley said.

“One 1.2-litre vehicle had similar on-road fuel consumption to several 2-litre cars, and a hybrid SUV had higher petrol consumption than a similar-sized conventional SUV.

“These tests show that when comparing vehicles, consumers and fleets cannot assume that vehicle performance as assessed by mandatory lab tests will translate into real-world savings or emissions reduction.”

Currently, information about a vehicle’s fuel consumption and emissions is based on laboratory tests conducted for car makers overseas and consumers have no way to assess how that information translates to actual performance of vehicles in Australian road conditions.

As with the previous rounds, vehicles selected for the third tranche of testing were tested in-and-around Geelong, Victoria, using strict testing protocols based on a similar real-world testing program already in place in the European Union, with some adaptation for local conditions.

The tests, which were developed in consultation with industry and the Commonwealth, are designed to deliver a high level of consistency when testing different vehicles.

The latest round of test results brings the number of vehicles tested under the RWTP to 43, with the initiative aiming to examine 200 cars, utes and vans over four-years. The program is funded by the Australian Government which has committed $14 million to the testing.

The results of all three rounds of testing are now available on the AAA website, with the RACQ and other AAA member clubs committed to promoting these and subsequent real-world test results to the nearly nine million motoring club members across Australia.

For more information, visit AAA Real-World Testing Program.

Disclaimer: Relevant vehicle brands were notified prior to the publication of any testing results. The information in this article has been prepared for general information purposes only and is not intended as legal advice or specific advice to any particular person. Before acting on anything based on this information you should consider its appropriateness to you, having regard to your objectives and needs. The information within this article is only correct as at the date of publication.