Liv Tyler's mom and one time manager, Bebe Buell, is not a fan of how Dina Lohan raised Lindsay ... and she's talking about her disapproval of Lilo's upbringing to Steppin' Out magazine.

Buell, who had Liv with rocker Steven Tyler, tells the mag:

    "Dina Lohan's relationship with her daughter Lindsay disturbs me. I don't see a mother and a daughter there. If my beautiful daughter was like that.... I mean Lindsay and Liv were practically born on the same day ... But if my baby girl got that screwed up I would NOT allow to make her own decisions. I'm sorry!"

The 1974 Playboy Playmate of the Month, who says she could help Lilo win an Oscar under her guidance, adds, "What her mother has done with Lindsay is morally wrong and disgusting. She should back off."

Those sound like fighting words! Click thru to read more of Bebe's hardcore interview.