Mine went at 92k. Last Christmas. It was all in the crankcase. I changed the lower intake gaskets, head gaskets and had the heads cleaned and checked for cracks and warpage. That was last Christmas. I now have 120k and the engine has never been loud at all. I have some very MINOR piston slap at startup for about the first minute in the morning and thats it.
If its burning the coolant, then its probably the lower intake. These engines, as I have found out, are BAD about this.
I run Mobil1 in mine and its all highway miles, might be why it still runs so quiet.