ATS
| ATS | 5 |
ATSF
| Atchison Topeka & Santa Fe | 4 |
BN
| Burlington Northern | 5 |
BNSF
| BNSF Railway | 13 |
CMCD
| CMCD | 2 |
DGNO
| Dallas Garland & Northeastern | 5 |
GREX
| Georgetown Rail Equipment Company | 40 |
GRR
| Georgetown Railroad Company | 2 |
HTT
| Harsco Track Technologies | 9 |
HZGX
| Herzog Contracting Corporation | 10 |
KBR
| KBR | 6 |
KCS
| Kansas City Southern | 4 |
MRL
| Montana Rail Link | 11 |
NORD
| NORD | 3 |
RELA
| RELA | 1 |
SPSX
| Progress Rail Services Corp | 14 |
UP
| Union Pacific Railroad Company | 9 |
WMRY
| WMRY | 1 |
WT
| Wrightsville & Tennille | 12 |