| Year | Class | Railroad | Horsepower | Notes |
|---|---|---|---|---|
| 1915 | EF-1/EP-1 | Milwaukee Road | 3,000 | HP total for 2 units |
| 1917 | EP-2 | Milwaukee Road | 3,200 | The Bipolars |
| 1919 | EP-3 | Milwaukee Road | 3,400 | |
| 1932 | EF-2/EF-3 | Milwaukee Road | 5,010 | HP total for 3 units |
| 1950 | EF-5 | Milwaukee Road | 6,680 | HP total for 4 units |
| 1948-50 | EF-4/EP-4 | Milwaukee Road | 5,550 | The "Little Joes" |
| 1947 | W-1 | Great Northern | 5,150 | |
| 1948 | EL-2B | Virginian | 6,800 | |
| ? | E33 | Virginian | 3,300 | sold to N.H. transferred to Conrail |
| 1917 | FF-1 | Pennsylvania | 4,000 | |
| 1924 | L5 | Pennsylvania | 3,070 | |
| 1927 | L6 | Pennsylvania | 2,500 | |
| 1927 | P5 | Pennsylvania | 3,750 | |
| 1927 | O1 | Pennsylvania | 2,500 | |
| 1934 | R1 | Pennsylvania | 5,000 | |
| 1934 | GG-1 | Pennsylvania | 4,620 | |
| 1937 | P5b | Pennsylvania | 5,300 | |
| 1938 | DD-1 | Pennsylvania | 5,000 | |
| ? | E44 | Pennsylvania | 4,400 |