- b low n , ▁mechan ically - asp ir ated ▁ 2 - stroke ▁ 4 5 - deg ree ▁V - type , ▁with ▁an ▁, ▁bore ▁by ▁stroke , ▁giving ▁ ▁disp lacement ▁per ▁cyl inder , ▁remained ▁in ▁production ▁until ▁ 1 9 6 6 . ▁Two ▁D . C . ▁gener ators , ▁one ▁per ▁engine , ▁provide ▁power ▁to ▁four ▁mot ors , ▁two ▁on ▁each ▁tr uck , ▁in ▁an ▁A 1 A - A 1 A ▁arrangement . ▁This ▁tr uck ▁design ▁was ▁used ▁on ▁all ▁E ▁units ▁and ▁on ▁MP ▁ 7 1 0 0 ▁and ▁C B & Q ▁ 9 9 0 8 ▁power ▁cars . ▁E MD ▁has ▁built ▁all ▁of ▁its ▁major ▁components ▁since ▁ 1 9 3 9 . ▁ ▁Operation ▁ ▁The ▁E 9 ▁power ed ▁American ▁passenger ▁and ▁mail ▁trains ▁from ▁the ▁ 1 9 5 0 s ▁into ▁the ▁late ▁ 1 9 7 0 s . ▁Many ▁of ▁America ' s ▁fin est ▁trains ▁— ▁such ▁as ▁Union ▁Pacific ▁Rail road ' s ▁" City " ▁fleet , ▁Bur ling ton ' s ▁" Ze ph yr " ▁fleet ▁and ▁Southern ▁Pacific ▁Rail road ' s ▁Coast ▁Day light ▁and ▁Sun set ▁Limited ▁— ▁had ▁E 9 s ▁pulling ▁them . ▁E 9 s ▁and ▁their ▁E 7 ▁and ▁E 8 ▁kin ▁ran ▁throughout ▁the ▁country ▁on ▁less er - known ▁passenger ▁trains , ▁Chicago ' s ▁network ▁of ▁comm uter ▁trains ▁and ▁many ▁mail