Diesel used to be the obvious choice for anyone towing or doing highway km. But with petrol engines getting more efficient and hybrids entering the picture, the answer isn't so simple anymore.
Quick Answer
- Buy diesel if: You tow regularly (2,000kg+), drive 25,000+ km/year mostly highway, or need maximum low-end torque for work
- Buy petrol if: You mostly drive in the city, do under 15,000 km/year, or want lower upfront cost and cheaper servicing
- Buy hybrid if: You want the best of both worlds for suburban/city driving with occasional highway trips
Fuel Cost Comparison (15,000 km/year)
| Example | Fuel Use | Fuel Price | Annual Cost |
|---|---|---|---|
| Ranger 2.0L Diesel | 7.4L/100km | $1.85/L | $2,055 |
| RAV4 2.5L Petrol | 8.0L/100km | $1.90/L | $2,280 |
| RAV4 Hybrid | 4.8L/100km | $1.90/L | $1,368 |
| Tesla Model Y (EV) | 15kWh/100km | $0.30/kWh | $675 |
Diesel saves $200/year over petrol. But the hybrid saves $700/year over diesel. And the EV saves $1,380/year over diesel.
Where Diesel Still Wins
- Towing. diesel engines produce peak torque at low RPM, which is exactly what you need when towing heavy loads up hills. A diesel Ranger at 500Nm vs a petrol RAV4 at 250Nm. the diesel barely notices a 2,000kg caravan
- Highway range. diesel cars get 800-1,200km per tank on the highway, vs 500-700km for petrol. For outback touring, this matters
- Durability under load. diesel engines are built stronger to handle higher compression ratios. They last longer under sustained heavy work
Where Petrol Wins
- Purchase price. petrol variants are typically $2,000-5,000 cheaper than diesel equivalents
- Servicing cost. no DPF filter, no AdBlue, simpler fuel system. Diesel servicing costs 15-30% more
- City driving. petrol engines are smoother, quieter, and more suited to stop-start traffic. Diesel DPF filters can clog with short city trips
- Refinement. modern petrol engines are quieter and smoother than even the best diesels
The DPF Problem
If you only do short city trips in a diesel, the DPF (Diesel Particulate Filter) can't reach operating temperature to burn off soot. This causes expensive blockages ($2,000-5,000 to replace). If your average trip is under 20 minutes, don't buy a diesel.
Compare Fuel Costs for Any Car
Our Fuel Cost Calculator lets you compare annual fuel costs for any combination of diesel, petrol, hybrid, and electric vehicles based on your actual driving distance.
Use the Speed vs Range calculator to see how highway speed affects fuel economy for both diesel and petrol.
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Disclaimer: All information in this article was believed to be correct at the time of publishing (22 March 2026). Prices are manufacturer recommended retail prices (RRP) and may vary by state, dealer, and options. Specifications, government incentives, and rebates can change without notice. Always verify details with the manufacturer or relevant authority before making a purchase decision. Running cost estimates are based on average Australian driving conditions at 15,000 km/year. All opinions are editorial and independent. CarSorted does not accept payment for recommendations or rankings.
Published by CarSorted Editorial Team · 22 March 2026
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