Other manufacturers require spec-specific oils (BMW LL-01/04, MB 228/229.x, Honda HTO-04), etc. Why shouldn't GM? These other specs are required for warranty maintenance, etc., and can be avoided at the owner's choice as desired after the warranty expires. GM has actually been a leader in extended OCIs in the USA, as the saab 9-3 has used the GM-LL-025-A in the US successfully (verified via UOA) brought forth extended OCIs, and improvements in the engine oil quality will mean that the non-premium, typical consumer will be able to utilize such operations.