If available, nothing wrong with RoyalPurple HPS oils.
Consider any BRAND A3/B4 oil, 0w30, 5w30, 0w40, 5w40 for example:
Castrol® Edge Euro Car is an advanced full synthetic motor oil formulated to improve engine durability in European cars. Find out if you can benefit from switching to Castrol Edge Euro Car formula.
Valvoline European Vehicle Full Synthetic Motor Oil is designed specifically to meet and exceed the demanding requirements of most European gasoline and diesel engine manufacturers. Our exclusive formula uses top wear additives, premium antioxidants and added detergents to fight wear, resist oil...
Pennzoil Platinum Euro Full Synthetic oil is designed for modern light duty diesel and high-performance engines in 0W-20, 0W-30, 0W-40, 5W-30 and 5W-40 viscosities.
I'd also consider:
Mobil 1™ FS 0W-40 motor oil is the result of decades of collaborative development with major car manufacturers and the application of the latest lubrication technology. It helps provide unsurpassed performance under very demanding driving conditions.
Mobil 1™ Turbo Diesel Truck 5W-40 is a fully synthetic diesel oil that helps extend engine life for modern diesel engines operating in severe applications.
Also, Ford's Powerstroke list of oils have various grades to choose from in their list, and their statement is also a good read:
And, since your location might not be shipping friendly, the 5w30uhp or 5w40uhp:
DURON UHP Ultra High Performance Heavy Duty Diesel Engine Oils. Read more.
You should gather UOA data trends with your Amsoil z-rod stuff, and then compare to the 5w40uhp, FS-0w40, or Edge A3/B4, and see if you'll still keep that z addiction.
Dose this with any temporary current spec full synthetic oil you pick.... maybe 2-3 ounces per gallon of oil: But, I prefer a properly blended oil and not blind additive dosing.. but the product is there if you're waiting on your Amsoil shipment:
Rislone's Award Winning Engine Compression Repair with Ring Seal Renews Worn Engines and Rebuilds Lost Power. Rislone's Been Protecting Engines since 1921.