I bought my 90 Carat with 125K miles = (plus however many more they put on because the odometer was broken) last = September while it was still hot. I have been holding my breath as the = weather turned colder because the DPO had never heard of coolant changes, and = there were some dry greenish stains around the head gasket. The weather got = down to the 30's for the first time last night, and there was a little coin = sized present on the concrete floor this morning. There was even some = coolant drops clinging to the oil filter, so I am hoping that maybe I only have = to replace the oil / water heat exchanger. However, I am getting this = ill feeling in my stomach that the heads are on their way out, and I need to = know: