Melissa McCarthy and New Line have turned to a comic legend to complete the cast of their laffer “Tammy” as Dan Aykroyd is in negotiations to join the project.

Susan Sarandon and Mark Duplass are also on board, with McCarthy co-directing with spouse Ben Falcone. McCarthy and Falcone are also producing from a script they co-wrote.

Pic follows a woman who, after losing her job and learning that her husband has been unfaithful, hits the road with her profane, hard-drinking grandmother (Sarandon).

Aykroyd would play Duplass’ father, who encounters McCarthy and Sarandon on their road trip.

Production is set to start next month.

Aykroyd is repped by CAA and recently lent his voice to the annie “Legend of Oz: Dorothy’s Return.”