i have a 97 expedition with 4.6 triton and i have an oil leak leaking onto my catalystic converter and smoking i was told it was rear main seal so my buddy replaced it and wasnt the problem so now my buddy thinks its the right bank head gasket leakin i dont agree with him i use to have my own shop and am VERY mechanically inclined but dew to double hip replacement cant do repairs any more . we checked valve covers no sign of leak so im thinkin intake but its so hard to see from underneath or above .has any one else had this problem and what did it end up being 270k on engine any help would be appreciated .is this a notorios problem for the 4.6 ?

 

this sounds kind dumb but did you check the PVC on the left side of the engine? my sisters 4.6 used to leak there and from the oil Caps it self...

 

yes i changed the pcv valve i think its a head gasket there is a large oil port that feeds the cam right where its leaking and 4.6's are bad for it appaerently but thanks any ways