Synthetic Oil that is made now is great forjust about any engine.Diesel engine Synthetic Oil rated typeis very good.The trouble is cleaning the oldoil out.It will need to be flush at least 4 to 6 times.The old oil all of it has to be removed.Remember to take the valve cover offalso and use a spay bottle to flush everythingclean.The oil pan also needs to be cleaned.I use it in mine and my wife's boat.A diesel engine is good for 8000 to 15000 hours if it is maintain.