There’s been an explosion in the sale of diesel vehicles in Australian. When you add the sale of diesel cars to that of diesel SUVs the growth is immense: diesel vehicle sales are up from about 92,000 in 2008 to more than 164,000 in 2013. That’s a jump of almost 80 per cent in a total vehicle market that has grown just 12 per cent in the same timeframe.
Why are so many people choosing diesel? Even more importantly, is diesel something you should consider? Here’s the top 10 things John Cadogan says you need to know:
- 1. Availability is higher
The simple fact is that more vehicles today are offering diesel drivetrains. More choice means more sales.
- 2. Diesel grew up
Diesel is no longer like grandad’s Massey Ferguson tractor. Modern diesel engines use hi-tech electronic injection control, common-rail piezo-electric injection systems and turbocharging for unprecedented performance and response.
- 3. It’s more fuel efficient
Diesels deliver roughly 30 per cent better economy than equivalent petrol engines. They have more compression, so the expansion part of the cycle occurs over a greater range, delivering better economy.
- 4. Diesel beats petrol at low revs
Diesels make three or four times the torque of a petrol engine at about 2000rpm. Because these are the revs you normally drive at, diesels feel unstoppable on hills, are ideal for towing and just generally pull without complaint. Petrols need to rev higher and even then usually can’t match the peak torque of the diesel.
- 5. Diesel and petrol cost about the same
Different factors affect the price of diesel and the price of petrol at the pump. Diesel is more closely linked to the state of the world economy. (When things are booming, demand for diesel increases, and so does the price.) But because diesel engines drink 30 per cent less fuel than petrols, you’re not really comparing apples and apples. However…
- 6. Diesels cost more up front
It’s usually $2500-$5000 more for the diesel. The engine is more sophisticated, and needs to be more robust, and is produced in lower volumes - hence the additional up-front cost. But this is not all bad news because…
- 7. You get some of that additional cost back
When you sell the car, some of the premium you paid up front (new) is reflected in the value of the asset (used). In other words a used diesel Car A is worth more than a used petrol Car A … all other variables being equal.
- 8. Petrol is playing catch-up
The other big difference is where the fuel and air mix. In most petrol engines the fuel is squirted into the air just before it enters the combustion chamber. In diesels the fuel gets squirted directly into the combustion chamber at the last minute. This is called ‘direct injection’. Some petrol engines now feature direct injection technology - which has improved their performance and economy.
- 9. The diesel pump is harder to find
Diesel pumps out-number petrol pumps about eight to one - so, at an unfamiliar service station the diesel pump is always harder to find. It’s also dirtier, too, because diesel doesn’t evaporate like petrol does. You’ll smell like eau d’diesel after re-fuelling
- 10. The exhaust could be a problem
Diesels have particle filters in the exhaust to trap microscopic particles harmful to human health. Some highway running (say, every two weeks) is required for the filter to heat up sufficiently to burn off these injurious particles. (They call it ‘regeneration’.) If you don’t do that, the filter could clog and you’ll need a trip to the dealer to sort it out. So, if you do only short trips in the city, diesel might not be for you.