I drive a SsangYong Musso, and the speedometer consistently reads a few miles per hour above my satnav. I have always believed that the satnav would be the most accurate and reliable, but I recently ...

Here's how car speedometers calculate how fast your vehicle is going. And here's why they may not always be accurate.

Sometimes, the factory speedometer isn’t an option. Maybe you’re trying different wheel and tire combinations that throw off calibration. Maybe the gauge cluster finally gave up the ghost. Or maybe ...