Any oil with the proper ratings will work. I have run Motorcraft, Magnatech, Valvoline syn high mile oil, Mobil1 High mileage and QSUD. Via the seat of the pants dyno what ever value it has is the QSUD and the Magnatech are my favorites which doesn't mean anything. The next oil change will be the Shell Rotella gas truck which I bought at closeout.
The dealer apparently did an oil change before we bought it with only god knows what kind of oil was used
I drained and filled with RGT 5-30 and installed a new MC filter
Maybe RGT is the best of what I’m looking for