The average price of a used diesel car fell by 10.3% between Q1 2017 and Q4 2018.
Diesel car values dropped 5% through 2017, on the back of consistent negative news about the fuel, and new data shows that slump continued through 2018 at a near-identical rate.
The analysis from car buying comparison website Motorway.co.uk also shows equivalent used petrol prices increasing 10% between Q1 2017 and Q4 2018, suggesting a fundamental change in mass consumer sentiment away from diesel towards petrol. This is now a clear trend over two years that shows no signs of changing.
Motorway.co.uk analysed two years of valuations for more than 130,000 used cars valued on its website, which aggregates live offers from popular online car buying websites and used car dealers.
Looking at the most popular makes valued during 2017 and 2018, most major car brands including Ford, Mercedes and Volkswagen saw diesel price drops, with the biggest falls seen with Land Rover, BMW, Vauxhall & Audi.
The average price of a used BMW diesel car has slumped by 16.1% since the start of 2017, falling almost £3,000 from £17,269 in Q1 2017 to £14,441 in Q4 2018. This compares with average prices of BMW petrol variants which have remained steady, falling just 0.6%, over the same period. While the average price of a diesel Audi has fallen 14.3% since the beginning of 2017, compared to a 8.4% increase in price for the petrol variants.
The average price of a Land Rover – almost all of which are diesel-powered – was down more than £6,000 from £30,493 to £24,399 between Q1 2017 and Q4 2018, a fall of 20%.