After looking at reviews of the Schaeffer Oil products, I went and ordered a supply of it. ->
https://www.schaefferoil.com/ Enough to switch over all the vehicles to it. So I got some 5W-20 and 5W-30. If it weren't for the hemi in the Trailhawk, I would have just gotten the 5W-30. Oh well.
Sounds like pretty impressive stuff!
Got some links to technical bulletins on both weights of the oil, if anyone is interested.
https://www.schaefferoil.com/documents/247-9003D-td.pdf
https://www.schaefferoil.com/documents/254-9004-td.pdf
But I had to order it directly from the manufacturer, since there doesn't seem to be a local supplier handy. But on the plus side, the rep I talked to gave me a pretty good deal on the order. Ask for Kevin James if you call there.