Why does speed differ on sat-navs?
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I HAVE JUST read your editorial in CM 30 August but, while I agree that too many drivers tailgate, I must ask a question: was your speed of 50mph taken from your car’s speedo or from a sat-nav? In my Nissan Navara – and in other cars I have driven – the speed on the car speedo is always a percentage higher than that shown by the sat-nav.
So when driving in your car at 50mph, your actual speed could be around 45mph (potentially). This makes the car appear more fueleficient. And car manufacturers could well be encouraging drivers into getting services more often than they would otherwise need to. Andy Jenkins Director, SE Davis & Son
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