Cost of Diesel vs Petrol when purchasing new car

[pologti18t]

Gave this a quick read... interesting numbers

Diesel cars: buyers guide | carsguide.com.au

[ralp2dam]

Gave this a quick read... interesting numbers

Diesel cars: buyers guide | carsguide.com.au

Good article thanks mate. I'm sure it will assist people having difficulty between picking between petrol & diesel.

[wai]

There was also something in the Herald Sun yesterday.

There is the purchase price that is a higher, however it is in the operating costs that there is a significant saving.

The article in the HS talked about standard ULP which some petrol engine cars recommend, however in Sydney for example, you cannot get standard ULP. You can only get E10. E10 is useless. You use around 10% more which negates the 10% less petrol in the blend PLUS the ethanol that is being burnt. Then there is the leaning of the mixture. As the ethanol is burnt, the oxygen is released from it and this has the effect of leaning the mixture. This makes the engine run more rough. If you tune the engine for E10, then as soon as you are out of the metropolitan area, you cannot get it, only standard ULP so now the mixture is too rich. The result is that you have to use Premium ULP which is around the same price as diesel or slightly more.

On the emissions side, E10 produces less unburnt hydrocarbons, and less carbon monoxide, however the nitrogen oxides more than double because of the higher temperatures from the leaner mixture. It is the NOx that gives you the brown haze (photochemical smog).

The other thing is on sizing of diesel engines. Some manufacturers offering them have them either size for size (or very slightly smaller) compared to their petrol engines. This is mainly because to use the low rev torque of a diesel, you need more gears, and they are still offering the same transmissions they do for petrol engined cars. As a result, you don't get anywhere near the benefits in fuel economy.

The article is very useful and people will eventually find this out. You also have to realise that a lot of copy in motoring magazines (online and printed) comes from car the manufacturers. All I know is that I am saving and will continue to save. I am using around half the fuel I used to use, and I will be having to service the car around 1/4 as frequently. Yes, service costs will be higher, but not 4 times higher.