AOK
| Arkansas-Oklahoma Railroad | 1 |
ARR
| Alaska Railroad | 1 |
ATW
| Atlantic and Western | 2 |
BNSF
| BNSF Railway | 4 |
DODX
| Department Of Defense | 3 |
FTSX
| Fairmont Tamper | 1 |
KRL
| Kasgro Rail Lines | 1 |
MILW
| Milwaukee Road | 2 |
NS
| Norfolk Southern | 2 |
PRR
| Pennsylvania Railroad | 1 |
RUT
| Vermont Railway Incorporated | 1 |
SOO
| Soo Line | 2 |
SOU
| Southern | 1 |
XTTX
| TTX Company | 1 |