Should we stick with petrol or go diesel?

Hi there,

We do annual mileage of about 11 or 12k. During the week the daily mileage is only about 20 miles or so and on slower roads so speed only about 80km/h max. We would do bigger mileage some weekends on motorway. My question is, would we run into problems with a diesel car? We currently have petrol but looking to update to a bigger car with a 1.4-1.6-litre range. However, there are very few petrol car options it appears suitable for family size. All the options seem to be diesel, which is fine, but I have heard that there can be mechanical issues if mileage and speed is not sufficient. Is that true?

Any advice much appreciated. What car options would you recommend to look at if going petrol or diesel?

Tomas Best (Dublin)

Jan 2018 Filed under: petrol vs. diesel

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Expert answer

Hi Tomas,

Yes, it is an issue and could potentially be a very serious issue with your kind of mileage and driving profile. The problem is that you need to generate heat in the exhaust system to keep the diesel particulate filter clear, and low mileages and low speeds just don’t do that. You can get around that, a bit, by doing a regular long motorway or main road run, keeping to a low-ish gear for a while, but that’s not convenient for everyone.

Basically speaking, I think you’re best sticking with petrol if at all possible and there are some big-car petrol options out there if you look around and get a little lucky. Try and track down a Skoda Octavia with the 1.2 TSI turbo petrol engine, perhaps? Or maybe consider a Toyota Prius — they’re pretty big inside (although the boot is not massive).

Neil Briscoe - Complete Car Advisor
@neilmbriscoe