Here's what I am running in my 2024 Ram 3500 6.4l.
Royal Purple #20-500, as others have stated; Its the same thread M22-1.50 and gasket, but the canister is a little longer at 4½". To me this makes it a little easier to access. For oil, I'm using Mobil1 European Car formula Mobil1 FS 0W-40. This oil is compliant with the API 'SP' spec, although all the info and pictures online don't say this. The 'SP' spec is new, and seems to be concerned with extra wear-protection on certain components (time chain, etc). It looks to me like this takes the form of high phosphorus (1,000 ppm) and zinc (1,100 ppm) additive levels, about 50% higher than what is in standard synthetic oils, but still less than what you'd expect in a racing-type oil. Plus some Moly, Boron, and Magnesium
From the spec:
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Product Description
Mobil 1™ FS 0W-40 European Car Formula is an advanced full synthetic motor oil engineered for the latest gasoline and diesel (without Diesel Particulate Filters or DPFs) engine technology delivering excellent all-round performance. It provides exceptional cleaning power, wear protection and overall performance. Mobil 1 FS 0W-40 keeps your engine running like new and protects for 10,000 miles*
Mobil 1™ FS 0W-40 is recommended by ExxonMobil for all types of vehicles, including high-performance turbo-charged, supercharged gasoline and certain diesel multi-valve fuel injected engines found in passenger cars, SUVs, light vans and trucks.
Meets or Exceeds:
AAE (STO 003) Group B7
API SJ
API SL
API SM
API SN
API SN PLUS
API SP
ACEA A3/B4
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Note that this appears to be a new formulation for the 0W-40 European Car Formula . You can compare both the older one (higher Calcium content, API SN classification) and revised formula specs here at this very handy spreadsheet:
https://docs.google.com/spreadsheet...fNRMFs8p7BY3L3iesQg/edit?pli=1#gid=2045175551. Go to the '40 Grade' tab.