Coming home the other day my car started slowly overheating a few blocks from my house, upon getting home me and my stepdad found coolant flowing out the back of the engine(side facing the rear of the car). To the point where there was literally a pool. We can't see where it is coming from so I'm assuming a Expansion/Freeze plug on the back since so much came out at once(I'm assuming if it were a gasket the oil and coolant would mix and/or it would be a slower leak and not happen out of nowhere). The plugs would be 211k miles old. I plan to take it to a mechanic when I get the chance to have it tested, but if it is indeed the rear expansion plugs, has anyone fixed this on their 3800? I've heard it's difficult. Or if someone has taken it to a shop what would be a general estimate? I've heard the engine needs to be pulled and I feel like that would cost a lot.
