Martin Lewis has claimed petrol and diesel owners could make savings at the fuel pump by making a slight change to their driving habits.
According to the money saving expert, it may be possible to save on petrol and diesel costs by simply topping up their car earlier in the day.
He made the revelation whilst reading letters from expert salespeople on his BBC Martin Lewis Podcast.
One listener contacted Martin to reveal the staggering hack as he called upon experts to reveal hidden secrets.
The finance guru admitted he had “heard this tip before” before passing over the advice on air.
Reading a letter from a listener called Paula, Martin said: “I learned when working at a petrol station, it’s an excellent idea to visit the gas station early in the morning and late at night when it’s cold outside.
“And it’s true, colder fuel has a higher density. In fact, a litre of cold petrol or diesel will weigh more than a litre of a warm one.
“Since you are paying for the fuel per volume, not per weight, it makes sense filling up in the morning and bringing in more fuel for the same price because there is more fuel in the same litre. So when it’s cold, fill up.”
Consumer Reports conducted an experiment to test the concept back in 2008.
However, they found that the change in temperature later in the day made little difference to the amount of fuel they obtained.
According to their findings, a 15-degree Fahrenheit difference resulted in a slight one percent gain in the volume pumped out. But, this would only be the case if petrol is stirred in cooler conditions which is usually not the case.
Fuel is instead held in large underground tanks which are more than capable of keeping it slightly warmed up before it is sold.
Craig Eerkes, former chairman of the Petroleum Marketers Association of America also weighed in on the issue.
Although, the expert admitted the difference would be “so minuscule” that it would be “almost nonexistent.”
The hack comes as fuel prices continue to remain high with average petrol costs now standing at 139.7p per litre, according to RAC Fuel Watch.
Costs have gradually fallen from highs of 191p per litre in July 2022 but figures are still higher than autumn 2021.
