| 1 | TTZX | Trailer Train Co. | eliminated 1/1992 | | NAKINA |
| 2 | TTZX | TTX Co. | added 1/1992; 1/1994-7/2005 | | NAKINA |
| 3 | TTZX | Trailer Train Co./TTX Co. (flat cars equipped with bulkheads and centre beams with tie-down systems for lumber loading) | 10/1991-1/1994 | | NAKINA |
| 4 | TTZX | TTX Co. (flat cars equipped with bulkheads and centre beams with tie-down systems for lumber loading, equipped with end of car cush.) | 7/2000 | | NAKINA |
| 5 | TTZX | Trailer Train Co. | eliminated 1/92 | | NRHS |
| 6 | TTZX | TTX Co. | added 1/92 | | NRHS |
| 7 | TTZX | TTX Co. (flat cars equipped with bulkheads and centre beams with tie-down systems for lumber loading) | Jan-94 | | NRHS |
| 8 | TTZX | TTX Co. (flat cars equipped with bulkheads and centre beams with tie-down systems for lumber loading, equipped with end of car cush.) | Jul-00 | | NRHS |
| 9 | TTZX | TTX COMPANY {TRAILER TRAIN COMPANY} | | | PWRC |
| 10 | TTZX | Trailer Train (TTX Corporation) | | | RSRV |
| 11 | TTZX | TTX COMPANY | | | SCAC4 |