Martin Lewis says you can cut cost of petrol or diesel by almost a third

Martin Lewis says you can cut cost of petrol or diesel by almost a thirdPrices continue to rise at the pump thanks to the war in IranCommentsMoneyNeil Shaw Assistant Editor (Money and Lifestyle)08:36, 13 Apr 2026View 3 ImagesMartin Lewis has advice on driving costsMoney Saving Expert Martin Lewis has explained how to cut the cost of your driving by up to 30 per cent. Most drivers assume cutting petrol or diesel costs means driving less, but personal finance expert Martin Lewis says small changes to how you use your car could make a far bigger difference than people realise. In a clip shared on his official TikTok, the MoneySavingExpert founder explained that everyday habits, from what you keep in your car to how you drive, can quietly push up your fuel bills. Ignore them and you could be spending far more than necessary. Get them right and the savings can quickly add up.‌Martin says improving efficiency and driving style together could cut fuel costs by “10% to 30%… depending on where you start,” making it well worth paying attention while prices remain high. Martin broke it down into simple, practical fixes, starting with something many drivers overlook.‌“Junk in your trunk,” he said, warning that unnecessary weight in your car is costing you money. “Extra weight, for every about 45 kilograms, makes your car 1% less fuel efficient.”‌View 3 ImagesAn employee holds a fuel nozzle at a petrol pumpIn the video shared on TikTok he also pointed to roof racks as a hidden drain on fuel. If they are not being used, they should come off. “You’re having to push that through the wind on a motorway as you drive,” he explained, highlighting how added drag forces your car to work harder. Tyres are another key area. Spotting under-inflated tyres, Martin said: “That can add 3% or 4% to your fuel bills,” urging drivers to keep them properly pumped up.Air conditioning, he added, depends on how you are driving. “When you’re going at low speeds, your aircon can be really quite expensive...