“Belt looked good”. NEVER let a positive visual inspection “prove” to you a belt is ok. The two belts I have changed looked excellent. All the markings could be read, the tiny cross hatches on the toothed side were pristine, yet they were both old, one documented over mileage and the other, well, no records but suspected original at 76,000 miles and probably 20 years of age. Once you’re in there, change the belt, it’s ultra cheap insurance, my belt cost £11, and unbelievable peace of mind. Nothing like being miles from home wondering if your belt is too old or over mileage.