I just bought a 2024 motorhome that's built on a Ford E450 super duty chassis with the 7.3l V8. I'm looking for a good filter for my first oil change. I plan on going 100% synthetic for oil - either M1 or possibly Castrol, not sure yet. But I have always purchased Wix XP filters in the past for my other vehicles. Wix shows the 51372 as the correct filter for that engine and chassis. When I looked for the 51372XP it's available at O'Reilly's which is right down the road, but their website says it doesn't fit my E450...huh? The XP line is for full synthetic oil, why would the regular 51372 fit but the XP won't? Is it because it's a super duty chassis? A bit confused at this point. To make it even more confusing there are two Motocraft filters listed for it, the FL820S and the FL1995A. Then there's M1 - they have two filters listed too, the M1-210A and the M1-601A. It looks like the FL1995A and M1-601A are longer filters. Runningn on a motorhome pulling a Jeep behind it maybe the extra oil would be a good idea? Suggestions?