Many of you spend much of your working lives on Britain’s motorways. But do you know which one consistently has the most expensive fuel?

Of course, downloading our special app will help you always find the cheapest fuel – wherever you are. Download it for free HERE.

It may help to plan your trips, however, if you know in advance that one UK motorway has been found to have the highest petrol prices over a seven-month period.

The M42’s service stations were found to charge drivers the highest petrol prices in five of the last seven months. To underline the point, one M42 motorway service station was found to be selling unleaded at 130.9p a litre – when the national average price was 107.5p.

It reinforced claims that this southern and eastern Birmingham ring road is Britain’s worst motorway. The 40-mile-long stretch was unfinished, falling 16 miles short of its link with the M1. It was also renowned for many years for its uniquely noisy concrete road surface. Thankfully, expensive remedial work has now largely rectified this problem.

And more research has shown that the M42 is a national black spot for tailgating — driving dangerously close to the car in front — and traffic delays, especially during evening rush hour