Ive been wondering this for a while, with fuel prices rising more and more people switching to Diesel cars, indeed for the first time new car sales has had Diesels in the majority in the UK, but is it a false economy?

In almost every case brand new the diesel variant of a car will cost more than its petrol equivalent, even with better fuel economy and lower VED it can take 1-3 years (even on medium-high mileage) to break even and then begin to see profit. Its maybe a bit closer on the used market but differences remain.

Right now on Auto Trader im looking at a 2008 Ford Focus 1.6 Zetec 5dr with Climate Pack, 17k on the clock and its £6485. Shift across to the diesel's for the almost identical car but TDCi instead and the cheapest is £7,995.

Lets work this out. The petrol one will apparently do 42.2mpg on average, so lets call it 40 as its rare cars exactly meet any figures. Meaning for 10,000 miles it'll cost (going by petrol at my local garage at 136.9) will cost £1,556 (give or take a few pence), and in VED band G at £165 a year. Meaning after 12 months its cost £8,206. Ok i know this is never going to be 100% scientific or accurate and yes theres servicing costs and any repairs needed etc but thats the same for both cars, im trying to see the benefit from diesel.

On the Diesel one, im actually comparing this to a 1.8 by the way as theres more of those in this search criteria, with a claimed mpg of 54.2, lets call it 51, to be fair, same difference as the petrol one, with diesel at 139.9, 10,000 miles comes to £1247. And £115 VED bill is also good, but still after 12 months, the Diesel one wouldve cost in total £9,357. More than a grand more.

Two years on and it stacks up at £9927 for the petrol and £10,719 for the Diesel. So still no return with the Diesel. Meaning its gaining on the petrol at around £300 a year just on VED and fuel.

Im not saying people shouldnt buy a diesel, some people prefer them, thats great, but does anyone else here think due to the growing popularity and therefore higher purchase price that diesel is something of a false economy especially for the mid-low range mileage user?