 | B&O GP40 | Baltimore and Ohio Railroad | | | 2 |
| BN GP40 | Burlington Northern | | | 2 |
| BN GP40M | Burlington Northern | | | 2 |
| BNSF GP40M | BNSF Railway | | | 2 |
| BPRR GP40 | Buffalo and Pittsburgh Railroad | | | 2 |
| CMNW GP40 | Chicago, Missouri and Western Railway | | | 2 |
| CNW GP40 | Chicago and North Western Transportation Company | | | 1 |
| CR GP40 | Conrail: Consolidated Rail Corporation | | | 2 |
| CRIP GP40 | Chicago, Rock Island and Pacific Railroad | | | 1 |
| DME GP40 | Dakota, Minnesota and Eastern Railroad | | | 3 |
| DRGW GP40 | Denver & Rio Grande Western Railroad | | | 10 |
| GWWR GP40 | Gateway Western Railway | | | 2 |
| HZGX GP38M-3 | Herzog Contracting Corporation | | | 4 |
| IC GP40 | Illinois Central Railroad | | | 3 |
| IC GP40 | Illinois Central Railroad | | | 0 |
| IC GP40R | Illinois Central Railroad | | | 2 |
| ICG GP40 | Illinois Central Gulf | | | 1 |
| KCS GP40 | Kansas City Southern Railway | | | 1 |
| MILW GP40 | Chicago, Milwaukee, St. Paul and Pacific Railroad | | | 4 |
| MKT GP40 | Missouri-Kansas-Texas | | | 9 |
| MNA GP40 | Missouri and Northern Arkansas Railroad | | | 1 |
| NW GP40 | Norfolk and Western Railway | | | 1 |
| PCC GP40 | Palouse River & Coulee City Railroad | | | 1 |
| PNWR GP40P-2 | Portland and Western Railroad | | | 1 |
| RF&P GP40 | Richmond, Fredericksburg and Potomac Railroad | | | 1 |
| SCL GP40 | Seaboard Coast Line Railroad | | | 2 |
| SOO GP40 | Soo Line Railroad | | | 4 |
| SWPX GP40 | Southwestern Portland Cement Company | | | 1 |
| UP GP40 | Union Pacific Railroad | | | 1 |
| WP GP40 | Western Pacific Railroad | | | 5 |
