Answer to "Leaking oil from the head gasket"Save yourself some money and remember this. Cummins head gaskets leak coolant, and rocker boxes leak oil. Although I haven't done a ton of engine work in the last fifteen years, up until then I did everything from general PM on Cummins, to overhauling a dozen or so a year. I constantly had drivers coming in complaining of head gaskets leaking oil and without exception it ended up being rocker boxes. I can't see the truck but I suspect you need a mechanic. Do yourself a favor and have the rockers sealed up and I bet you will be fine.