All I am saying are the tolerances in the bearings such that a 5w-40 is unnecessary and would a 5w-30 cj4 do just as well wear wise. The shearing of the oil seams to indicate the bearings are designed for a 30 weight oil and less shearing allows the 30 wt to run cooler and protect just as well.The "eco" tune refers to the lack of DPF on the vehicle, thus no need for a low ash oil. The UOA in that post is 90% highway miles. Car now runs quite a bit more city, but not stop and go traffic. If the the oil had sheared too much, would wear have gone up as well?
With the Eco tune you have a great opportunity to take advantage of a 5w-30 CJ4 oil that likely will last 15000 miles plus, provide equal protection and return improved fuel mileage because you have a roller cam and really no need for a 40 wt.