Interesting, as
@BULL put it.
. I don't know what that MSA0921 is. That seams like an internal Chrysler/FCA/Stellantis internal rating (I honestly mean, I dk) . The other earlier MS12633 seams like the same. Just like Mercedes Benz has it's MB229.5 or Volkswagen-Audi has it's VW505-00 ratings and company recommendations for oil. I assume those codes are internal company codes and they 'vetted' this brand of oil and give it an OK with there internal company code? Am I wrong?
I would be more concerned with the API rating like SP or SN or SN plus. But that's "confusing" also(not-really). I mean that it seams Mobil one was good enough for super charged Hellcats before (as long as API rating was correct), but now that FCA/Stellantis has their contract with Pennzoil that's their recommend. The only constant would be the API rating I would think.