As I read your first post, I thought, "Been there, done that. Bad head gasket." Know that it *could* be a small crack in the block, instead. That's what mine ended up being after the dealer machined both heads and replaced both gaskets. Hope yours is just the gasket.

 

That is good but I know for a fact that the fan clutch will slip as the spring in the housing gets old. It will just set still or just spin like it is working but the darn thing will not pull the air like it should. Some of those sound like an engine of there own when they startup with the heavy duty ones on an engine it does not need to be on. Have seen a vibration come from them as well as you watch the water pump shaft start to move around a little. In that case the water pump was bad mind you.
If it is man made it will go bad in time.