There is so much information out here, I am sure this has been talked about. I purchased a 2009 MCS with 30k on it. It has had the recall performed on it for the timing chain and I just changed the oil at the dealer. Before the oil temps reaches 100 to 105 degrees (ScanGauge II) the engine makes a very gurgle or bubble sound.

Normal?

 

Sounds like you have air trapped in the cooling system. Most likely you are hearing the air move through the heater core. Open the hood & check the coolant level. Add if needed. Do this on a COLD engine.