I have a 2004 cavalier with the 2.2l 4 cylinder and am looking to change the head gasket. I had a overheating incident, as well as being hard to start now and then. It other wise drives great though with no smoke or anything, but I do need to top off the coolant now and then. When I got the oil changed the mechanic told me the oil looked real nasty, and recently I just checked the coolant over flow and it looks weird so I'm guessing the oil has mixed with the coolant. I recently took it to a auto shop and they said it was def the head gasket as the the cooling system was reading 350 ppm hc. I always heard a blown head gasket would make alot of smoke but there's no smoke coming out the back.

Since this might send me back ~$2000, should I get anything else replaced while they change the gasket? Like I said the car runs great.

Thanks!