I have a Volvo S80 2.9 with 165,000 miles. I am the original owner. I still have the original radiator hoses and thermostat. It is time to replace the coolant. Local Volvo dealer says they only replace hoses if they break or present problems. My hoses look fine and do not seem to have any bubbles or problems. Should the hoses be replaced just because they are over 9 years of age? The thermostat also seems to work fine. I assume that adding coolant through the tank will flow into the radiator until it is full??? Thanks! Ted