[kathyricks]

Chains have chain tensioner problems too over time. Just like belts do. And replacing a chain mechanism is significantly more costly and labor intensive than changing a belt. Chains also stretch over time, retarding valve timing. Timing belts don't stretch. So there are pros and cons to chains vs. belts.

Unlike belt tensioners which come with sealed bearings, chain tensioners are lubricated by engine oil. So chain tensioner life is greatly influenced by oil change frequency. The owners who follow the tried and true 3-6 month / 3,000-5,000 mile rule with either dino or synthetic oil are the ones who typically get 400,000 miles or more of life out of their chain tensioner.