Recenly my Garage advised my daughter to fit a new cambelt to her Renault S Reg with 28000 miles on the clock. It cost her £375 and she is concerned whether or not to do likewise to her son's Matisse V Reg 30000 miles.
Surely the greatest wear on the belt is mileage and I wonder if garages are being alarmist or looking for trade

John O'Brien, November 2007

cam belt wear can be measured in two ways firstly by mileage as you already said but also the age of the belt is a factor. Alot of manufactors have a recommended time to change regardless of mileage. The belt is made from rubber and will degrade over time. The existing belt is now just over 7 years old so maybe time to change because if it were to break it would cost alot more for an engine rebuild, hope this helps.

Grant Scott, November 2007