As a kid, I loved balloons. They were great fun – you could throw them up and watch them float down, bop your friends over the head with them, and so on. However, I was always disappointed that my balloons didn’t last. They didn’t seem to have any holes or leaks in them, but over weeks they would shrivel up and stop being any fun to play with, as they slowly lost air and pressure.
The reason is that pretty much everything, no matter how well sealed, will eventually lose air. Your tyres are no different. Yes, they’re incredibly well sealed, and pumped full of lots of air so that you can drive safely. And they have to be – with all the turning they’re doing against rough bitumen, you can bet that they’re being squeezed hard between your vehicle and the road. So it makes sense that – like the balloon – they are slowly, imperceptibly, losing air.
It’s the “imperceptibly” that’s the tricky bit. If you could see it happening, then you could fix it. But you can’t see it happening unless you get a puncture, and what usually happens is that tyres deflate significantly before they get pumped back up.
The solution? Get a tyre pressure monitoring system. While the pressure loss in your tyres might slip past the naked eye, specialised tyre sensors will pick up on it and inform you that – would you look at that? – your tyres are actually quite deflated. And deflated tyres can be dangerous to drive with – your handling gets worse, and it takes longer to stop. Plus, the tyres wear down much faster if they don’t have enough air pressure. So with a TPMS you can make sure that they don’t get to that stage, since you’ll know when they are a little deflated, and you can fix it.