Cambelt or timing chain? How to know what your car has

Cambelts and timing chains do the same job — keeping your engine's valves and pistons in sync — but they wear out very differently. Get it wrong and you're looking at a four-figure engine rebuild.

Dry cambelts (rubber, external): typical interval 60,000 to 100,000 miles or 5 to 8 years. Common on older VW, Ford, Vauxhall and PSA engines.

Wet cambelts (rubber, running in oil): fitted to Ford EcoBoost 1.0 / 1.5 and PSA PureTech engines. These shed material into the oil and clog the pickup. If you drive one, we recommend replacement every 60,000 miles or 6 years, whichever comes first — and always with a fresh oil change.

Timing chains (metal, in oil): last the life of the engine in theory, but stretch is a real problem on BMW N47, VAG 1.4 TSI (EA111), Mini N14 and some Mercedes M271 engines. A rattle from cold on start-up is the classic warning sign.

Not sure which you have? Send us your reg on 01730 555 777 and we'll look it up in seconds. We replace belts, chains and wet belts at our West Harting workshop with a courtesy car included.