[Tatsfield]

Perhaps if Volvo owners shifted their mind set on thermostat replacement and looked at it in the same way as cam belt replacement then we would be routinely scheduling the work every 2 or 3 years regardless of whether we had discerned faults because by that time the thermostat might be pretty far gone and the effects of that would be costing us money in fuel etc any way although we might not notice the gradual drop off in performance over the long period of time it takes for the wax capsule to degrade and fail. What life expectation should we have for this ancient technology component? Whatever it turns out to be, we need to factor that into a routine maintenance and replacement schedule for our Volvos perhaps together with the coolant temperature sensor which also has dramatic effect on performance which can onset slowly with gradual degradation of the sensor before it actually fails.