Diesel vs Petrol (2026)
Diesel vs petrol in Australia: running costs, efficiency, DPF considerations, and who should choose which.
Key takeaways
Compare the exact vehicles you
Compare the exact vehicles you are considering rather than applying one national rule.
Use each vehicle's real fuel
Use each vehicle's real fuel consumption and current local pump price to estimate running cost.
Include servicing, registration, insu…
Include servicing, registration, insurance and purchase price in the comparison.
Check the manufacturer's maintenance and
Check the manufacturer's maintenance and diesel particulate filter guidance for your driving pattern.
Using this guide
Before you act on the guide
Check the station price, report time and distance before changing your route.
Start with the vehicle, not the litre price
Petrol and diesel vehicles can have different purchase prices, fuel use, servicing needs and towing capacity. Compare the exact models you are considering rather than applying one national rule.
Compare running cost
Use each vehicle's real fuel consumption and the local pump price to estimate cost per 100 kilometres. Include servicing, registration, insurance and expected annual distance before calculating a payback period.
Run the numbers for the exact models
Start with the combined fuel-consumption figure for each exact variant, then replace it with your own measured consumption if available. Multiply litres per 100 kilometres by the local litre price to compare fuel cost over the same distance. Apply your expected annual kilometres, not a generic national average. Treat the result as one line in the budget: ask for servicing schedules and quotes, check registration and insurance, and include the purchase-price difference before deciding.
Match the engine to your driving
Frequent short trips, long highway drives and towing place different demands on a vehicle. Check the manufacturer's maintenance requirements, including any diesel particulate filter guidance, and discuss an unfamiliar model with a qualified mechanic.
Check local pump prices
Diesel and petrol respond to different demand, wholesale and supply conditions, so their prices do not always move together. Use the fuel map for prices near you and rerun the comparison with the kilometres you actually drive.
Frequently asked questions
It depends on the exact vehicles, their real fuel use, current local prices, servicing costs and how far you drive. Compare cost per 100 kilometres and total ownership costs for the models you are considering.