I think the same culture would pervade anyone who is 2gen and greater American. Unless someone is 0-gen or 1-gen, they become Americanized (as any immigrant to a new country would become localized after 2 gens elsewhere). So unless they are recent immigrants or the children of those recent immigrants, even if they are not white, they would be culturally American.

On a side note, I think 1st gen have it the hardest of all. 0-gen know their standing and know they are newcomers with foreign customs. 1-gen often are in the middle and aren't sure where they belong culturally, here, or there. 2-gen usually don't have any such ambivalence.