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Not really, Valvoline, Pennzoil, Amsoil ASL (Amsoil XLF full syn, Group III, does not, but it meets the 6094 spec...go figure that one, since both are labeled full synthetic), and Castrol also meet the GM synthetic oil spec, in their respective FULL synthetic oils. There may be others too, but these I know for sure do meet the spec (4718).
In addition, Mobil 1 and Amsoil's ASL are the only two PAO/Group IV synthetic motor oils on the market. The remainder, including Amsoil's XLF are Group III hydro-cracked synthetic oils. This last bit of info basically means nothing since the important thing is the oil meets or exceeds the GM required spec.