Recently I have been considering running a XW-30 Euro oil in my Mustang GT with the 5.0, mainly because of the higher HTHS and beefier additive pack. The car is not tracked, but it is daily driven and driven hard at times reaching redline almost daily, sometimes several times in one day. It’s hard to resist when the Coyote spins to 7,500 RPM and the exhaust notes are beautiful paired with the 6sp manual. The thought of a higher HTHS and a beefier additive pack is appealing, but sometimes I wonder if it is necessary over the API SP ILSAC XW-30 oils I have been running. Oil is normally changed every 5K miles, but I’d consider 6-7k if I switched to a Euro oil as they are formulated to withstand a longer OCI from what I understand. I, like many others here, tend to overthink things (oil and maintenance) and choice of oil will not be the reason this car is no longer drivable someday. But when you are into your car and an enthusiast, you just want the best for it. So does my application call for a more stout Euro XW-30, or should I stick with the API ILSAC 30 grade oils? These oils cost the same at Walmart and the auto parts stores, so in my mind, why not run the more stout Euro oil?