If your car was built in the last few years, there's a good chance it has a "wet belt" — a timing belt that runs inside the engine, submerged in oil, rather than outside like a traditional cambelt. It's a design choice some manufacturers made to reduce friction and improve fuel economy, but it comes with a catch many drivers don't know about.

Wet belts degrade differently to conventional belts. Instead of giving obvious warning signs like cracking or fraying, they can shed small rubber particles into the oil, which — if left unchecked — can clog oil pathways and cause serious engine damage. And because the belt isn't visible without stripping down the engine, there's no simple visual check you can do yourself.

The manufacturer's recommended replacement interval is the one number that matters here — for many wet belt engines it's every 5 years or so, regardless of mileage. Skipping it isn't a small risk; a failed wet belt is one of the most expensive repairs we see. If you're not sure whether your car has one, ask us — we'll check for you.