Millions of drivers waste hundreds of pounds of fuel every year simply by improperly inflating their vehicle tires, a new study has found.
Technicians at a garage in Wales checked the tire pressures of 100 vehicles for maintenance over a month and discovered that 72 percent had not had their tires inflated to manufacturer’s recommended guidelines.
In 22 percent, all four tires were inflated to the wrong pressure.
Significantly, four in five cars and vans with incorrect tire pressure were under-inflated – a mistake that can make a vehicle up to 10 per cent less efficient and cost the driver of a petrol family car around £140 a year lead-free waste can cost.
A review of 100 vehicles requiring service between September and October found that almost three quarters (72%) had an incorrectly inflated tire
The analysis was carried out by the garage as part of a study by roadside assistance provider Green Flag.
It is estimated that the total cost of fuel wasted due to drivers incorrectly inflating their tires (whether just one or all four) in Britain is as much as £1.2 billion per year.
For motorists who were driving with all four tires at pressures lower than the manufacturer’s recommended level, the impact could be significantly costly to the fuel bill.
Philip Gomm, spokesperson for road safety organization RAC Foundation, explains: ‘Incorrectly inflated tires can be bad for safety, but also affect fuel consumption.
‘If they are too low, fuel consumption is reduced by as much as ten percent due to the extra resistance of the road.’
For a petrol family car returning 40 miles per gallon (mpg), the annual fuel cost (based on the current price of unleaded petrol at 150.69p, according to RAC Fuel Watch) is to cover the UK average mileage of 7,400 miles per year £1,267 .
But if under-inflated tires reduce fuel consumption by as much as 10 per cent, reducing consumption to 36mpg, the annual fuel bill would rise to £1,407, based on This is Money’s calculations.
Experts warn that underinflated tires can reduce a vehicle’s efficiency by as much as 10%. For the average family car owner, this could mean £140 worth of fuel wasted every year
While underinflation can be caused by a flat tire, it is usually the result of the owner’s negligence.
For owners of the latest models with tire pressure sensors on their cars, there is no excuse as their dashboard will tell them if they need to pump more air into one or more tires well below the approved level.
Every car has a recommended tire pressure, measured in Pounds per Square Inch (PSI), which varies depending on the make and model.
This recommendation is stated in the owner’s manual and is often located on the inside of the sill of a front door.
Green Flag’s research, carried out between September and October this year, found that motorists are driving their cars at pressures well outside the guidelines.
For the tires that were determined to be underinflated, the PSI was on average seven PSI lower. And for the overinflated tires, the average was five PSI above the recommended pressure.
Incredibly, some car tires tested were found to be 20 PSI below the vehicle manufacturer’s recommended figure, while others were up to 11 PSI above the recommended level.
Driving with underinflated tires comes with its own risks.
Severely underinflated tires can cause the tire to overheat and blow out the sidewall, causing rapid tire deflation and causing the driver to lose control of the vehicle. Improper tire pressure will also lead to irregular or premature tire wear, requiring more frequent replacement, Green Flag says.
And it’s not just the tires on the cars that are incorrectly inflated.
A third (32 percent) of the 100 vehicles requiring maintenance had a spare wheel.
However, only 28 percent of these were incorrectly inflated.
Although spare wheels and tires are disappearing almost as standard from new models, those lucky enough to have one are likely to run the risk of making this backup solution obsolete if the spare wheel in the boot is not suitable for mounting if the driver is unlucky has to get a flat tire.
The breakdown service says motorists should ensure that all tires – and not just those on all four wheels – are properly maintained so that they meet legal standards when in use.
Katie Lomas, chief executive of Green Flag, commented: ‘Our research shows that a worryingly high proportion of Britons are driving on incorrectly inflated tyres.
‘This can be incredibly dangerous and costly, so it is crucial that drivers check their car’s tire pressure regularly, especially if the car is fully loaded or if they are planning a long journey.
‘Cars naturally lose pressure over time, so it is important to check them regularly to ensure they are inflated correctly, in accordance with the manufacturer’s recommendations.’
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