When should you change the timing belt on a VW New Beetle?

The belt should be replaced between 60K and 70K. You should replace the water pump at that time also; the water pump has a plastic impeler that breaks. Find an aftermarket water pump with an upgraded metal impeller. You should also replace the coolant reservoir w/cap; the sensor (low coolant sensor) goes bad. Never mix different antifreeze fluids (you will get gummy substance in bottle and coolant lines). You should use the same one for the life of the car.