I noticed the other day when adding oil to my 2005 300C that there was moisture under the filler cap. I also noticed moisture on the oil dip stick. I ask the service tech. at the dealership about this and was told the this was common on the Hemi engines. Is this true and what can be done to stop it? I'm using Mobile 1synthetic oil. And no it's not engine coolent. Is there anything to add to the oil to get rid of this moisture?