Caution, I'm allowing my opinions to seep out here, so for goodness sake, don't beat me up for the generalizations I'm about to make ...
I see no reason not to run this oil in the Dmax. But that's partly because a Dmax is an engine that seems to care little about what oil it has in it. All quality HDEOs seem to provide good to stellar UOA results. As long as you use an HDEO in proper grade, the Dmax will like it.
As we most all realize, PSDs seem to be a bit more finicky. Not that they can't perform well, because many do, but for some reason PSDs seem to be more individually sensitive to certain HDEOs. One PSD might like MC oil, while the next likes Rotella, while the next likes Amsoil, and so on.
The Cummins seems to like any oil, but it certainly likes consistency of approach. In other words, you can pick any oil you want, and as long as you stick with it, the UOAs will be absolutely outstanding.
Hopping from oil to oil in a Cummins does not hurt anything, but it sometimes can give a bouncing effect in short term UOAs. But once you stick with an oil, they seem to become the Rock of Gibraltar in steady performance. A CTD can turn in some of the best UOAs you'll ever see, but they thrive on consistency of approach.
Running JD CI-4 oil in your Dmax likely won't hurt/help any more than running Delvac CJ-4. They all look good in a Dmax. Simply put, they are less finnicky about what you run in them.
Yeah, I drive a Dmax. But my neighbor runs a PSD, and a friend at work runs a Dodge. I enjoy the comparisons we do with UOAs, and the friendly "brand discussions" we get into.
But I've come to realize this: most any of today's well made engines run quite well with well made oil.
So, Cowhorse, to your point, as long as you can get it and it's reasonable in cost, there's no reason not to use it!
