One problem related to blown head gasket has been reported for the 2004 Volvo S80. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Volvo S80 based on all problems reported for the 2004 S80.
Car began overheating and eventually overheated and ruined engine later mechanic discovered thermostat wasnt working properly so no indication as to vehicle tempurature. Car was on freeway and stopped coming off freeway. Head gasket blew also as well as bad transmission.