▁manual ▁transm issions ▁were ▁offered ▁in ▁ 1 9 7 3 , ▁but ▁the ▁greatest ▁majority ▁of ▁C ut lass es ▁( including ▁Sup rem es ) ▁were ▁built ▁with ▁the ▁three - speed ▁Tur bo ▁H yd ra - m atic ▁automatic ▁transmission ▁which ▁became ▁standard ▁equipment ▁in ▁ 1 9 7 4 , ▁along ▁with ▁variable - rat io ▁power ▁ste ering . ▁ ▁The ▁ 1 9 7 3 - 7 4 ▁energy ▁crisis ▁resulting ▁from ▁the ▁Arab ▁O il ▁Emb argo ▁led ▁Old sm obile ▁to ▁introduce ▁two ▁new ▁smaller ▁engines ▁to ▁the ▁C ut lass ▁line ▁in ▁ 1 9 7 5 . ▁The ▁Che v ro let ▁built ▁ 2 5 0 ▁cub ic - inch ▁inline ▁six ▁and ▁three - speed ▁manual ▁transmission ▁were ▁re inst ated ▁as ▁standard ▁equipment ▁on ▁the ▁Supreme ▁cou pe ▁and ▁sedan ▁with ▁a ▁new ▁Old s - built ▁ 2 6 0 ▁cub ic - inch ▁Ro cket ▁V 8 ▁( standard ▁on ▁C ut lass ▁Sal on ▁and ▁optional ▁on ▁all ▁other ▁C ut lass es ▁except ▁w ag ons ) ▁offered ▁as ▁an ▁option . ▁However , ▁the ▁majority ▁of ▁C ut lass ▁Sup rem es ▁in ▁ 1 9 7 5 , ▁ 1 9 7 6 , ▁and ▁ 1 9 7 7 ▁were ▁sold ▁with ▁the ▁now - optional ▁ 3 5 0 ▁Ro cket ▁V 8 ▁and ▁Tur bo ▁H yd ra - m atic ▁automatic ▁( st ill ▁standard ▁on ▁w ag ons