Robert, as others have indicated you may not have a serious issue at all. A quick question and suggestion. How long does the truck set between drives? And if weeks at a time or it's generally only used to go short distances (3 or 4 miles) a monthly drive of 20 or so miles continuous driving will get everything up to temp, cooking off any moisture in the engine and oil as well as the differential and transmission. Worse thing we can do with our classic vehicles is not drive em.
Added as an afterthought. Change the oil to 15w40 diesel rated oil. It's good for the engine and may help.
Good Luck
RonR
Last edited by moparguy; 05/04/2019 1:53 PM.
