I bought a 07 Tribeca and the head gasket was done. The owner told me I didn’t have to worries because the dealership did it. Now 20K miles later It is overheating. What guarantee said they didn’t do a very good job, right?
It’s been 20,000 miles (and an unknown period of time). Have you been checking to make sure the coolant level is ok (radiator and overflow)? Was the thermostat replaced? A bad thermo could cause overheating too. You’ll have to look at the order slip from the last head gasket to see what the time/mileage warranty was from the shop.