| 1 | TTLX | Trailer Train Co. | added 1/1983; eliminated 1/1992 | | NAKINA |
| 2 | TTLX | TTX Co. | added 1/1992; 1/1994-7/2005 | | NAKINA |
| 3 | TTLX | Trailer Train Co. (flat cars specially equipped by participant railroads with container pedestals or fixed hitches for assigned corridor intermodal service under the control of assigned participant) | added 1/1983; 7/1985 | | NAKINA |
| 4 | TTLX | Trailer Train Co./TTX Co. (specially equipped intermodal flatcars) | 10/1991-7/2000 | | NAKINA |
| 5 | TTLX | Trailer Train Co. | added 1/83; eliminated 1/92 | | NRHS |
| 6 | TTLX | TTX Co. | added 1/92 | | NRHS |
| 7 | TTLX | TTX Co. (specially equipped intermodal flatcars) | 1/94-7/2000 | | NRHS |
| 8 | TTLX | TTX COMPANY {TRAILER TRAIN COMPANY} | | | PWRC |
| 9 | TTLX | Trailer Train (TTX Corporation) | | | RSRV |
| 10 | TTLX | TTX COMPANY | | | SCAC4 |
