The push to lower passenger car emissions in Australia began in earnest in 2025 with the introduction of the New Vehicle Efficiency Standard (NVES).
But even so, a perennial debate rages on: should I buy petrol or diesel? Even with the advent of hybrid, plug-in hybrid, electric and even hydrogen technologies in Australia, the reality is that new petrol and diesel cars remain the predominant choice for most Aussies. And furthermore, there’s still plenty of shelf life in them yet.
To help wade through all the confusion, we've put together a comparison of diesel and petrol cars, which covers factors including environment, running costs and intended use.
Let’s begin with the oil burners.
Although diesels aren’t as popular as they once were in Australia – partly because of less availability coming out of Europe and Asia, with more carmakers prioritising petrol drivetrains – the truth is they still have plenty of merit.
Even as recently as 20 years ago, the petrol engine was overlooked by many in favour of diesel, because it struggled to match the efficiency and pulling power.
However, with the advent of direct injection, turbocharging and variable compression ratios, the humble petrol is now much more versatile. And, with the advent of synthetic fuels, the petrol stands to be around for decades to come.
Here is why petrol is considered the better fuel source by many:
Newer diesel vehicles contain particulate filters that are supposed to catch the nasty particles of nitrogen dioxide which has been linked to cardiovascular and respiratory disease.
A 2018 report by The World Health Organisation stated ambient (outdoor) air pollution in both city and country areas causes up to 4.2 million premature deaths worldwide each year. Be sure to check your car's figures (if buying new) and the condition of the filter (if buying used).
When you look at the pros and cons of buying a diesel or petrol car, there's no simple way to determine which is better as it really depends on your personal circumstance and how you plan to use the vehicle. There are however, a few things to consider.