May 01, 2009· Best Answer: as stated its not an automatic, gm used those transmission in a lot of vehicles,it was the m22 or muncie four speed tranny which was used in everything from chevelle, SS,cars to impala SS cars,even some of the vega transmissions was m22,s, they was very popular back in the 60,s and 70,s,the reason they got the name rock crusher, was when you shifted them they sounded like .