Your citroen xantia has 77000 miles when do you change the cambelt?

The cambelt on a Citroën Xantia should typically be changed every 60,000 to 100,000 miles, depending on the specific engine model and manufacturer's recommendations. Since your vehicle has 77,000 miles, it's advisable to change the cambelt soon if it hasn't been done already, as waiting too long can lead to potential engine damage. Always refer to your owner's manual for the specific maintenance schedule for your model.