Autozone had a lot of types of Syntec, but two caught my eye. One was 0w30 European Formula, made in Germany. This is obviously German Castrol. The other was 5w40 European Formula. The back label said something like "European protection now formulated in the USA." Can I assume this is also German Castrol? It's the viscosity I want. Here are the specs from Castrol's website.
SAE 5W–40:
is engineered specifically to meet the Volkswagen engine warranty requirements, exceeding VW 502 00 and 505 00. Exceeds all car and light truck manufacturer’s warranty requirements for the protection for gasoline, diesel and turbocharged engines where API SL, SJ, SH, CF or CD is recommended. Exceeds European ACEA: A3, B3, B4, MB 229.3, MB 229.1, BMW LL-98, Porsche A40. Meets the engine protection requirements of Volvo, BMW, Mercedes Benz and ILSAC GF-3 for API Certified Gasoline Engine Oils.
SAE 5W–40:
is engineered specifically to meet the Volkswagen engine warranty requirements, exceeding VW 502 00 and 505 00. Exceeds all car and light truck manufacturer’s warranty requirements for the protection for gasoline, diesel and turbocharged engines where API SL, SJ, SH, CF or CD is recommended. Exceeds European ACEA: A3, B3, B4, MB 229.3, MB 229.1, BMW LL-98, Porsche A40. Meets the engine protection requirements of Volvo, BMW, Mercedes Benz and ILSAC GF-3 for API Certified Gasoline Engine Oils.