| 9501 | TTAL | TRANSPORT ALAIN SIGOUIN | | | SCAC4 |
| 9502 | TTAO | TRANSPORTES ARO | | | SCAC4 |
| 9503 | TTAR | TRANSTAINER CORPORATION | | | SCAC1 |
| 9504 | TTAR | TRACKDOWN TOWING & RECOVERY | | | SCAC4 |
| 9505 | TTAT | T & T TRANSPORTS INC | | | SCAC4 |
| 9506 | TTAU | TRET SRL | | I | BIC |
| 9507 | TTAU | TRET SPA | | | SCAC4 |
| 9508 | TTAX | Trailer Train Co. | added 4/1968; 10/1968-1/1980; eliminated 1/1992 | | NAKINA |
| 9509 | TTAX | TTX Co. | added 1/1992; 1/1994-7/2005 | | NAKINA |
| 9510 | TTAX | Trailer Train Co. | added 4/1968 | | NAKINA |
| 9511 | TTAX | Trailer Train Co. (89'4"" FC flats equipped with container adaptors, trailer hitches and bridge plates. Equipped with hydraulic draft gear) | 10/1968 | | NAKINA |
| 9512 | TTAX | Trailer Train Co. (flush deck flat cars equipped with movable foldaway container pedestals, knock-down hitches and bridge plates; for transporting trailers or containers or combinations of both) | 4/1970 | | NAKINA |
| 9513 | TTAX | Trailer Train Co. (flush deck flat cars equipped with foldaway container pedestals, knock-down hitches and bridge plates; for transporting trailers or containers or combinations of both) | 1/1975 | | NAKINA |
| 9514 | TTAX | Trailer Train Co. (flush deck flat cars equipped with foldaway container pedestals, hitches and bridge plates; for transporting trailers or containers or combinations of both) | 1/1980-7/1985 | | NAKINA |
| 9515 | TTAX | Trailer Train Co./TTX Co. (skeletonized, 5-unit, articulated all-purpose car for use between lift-on/lift-off facilities only, capable of carrying various combinations of trailers and/or containers of various lengths and widths) | 10/1991-7/2000 | | NAKINA |
| 9516 | TTAX | Trailer Train Co. | added 4/68 | | NRHS |
| 9517 | TTAX | Trailer Train Co. (89'4" FC flats equipped with container adaptors, trailer hitches and bridge plates. Equipped with hydraulic draft gear) | Oct-68 | | NRHS |
| 9518 | TTAX | Trailer Train Co. | Apr-70 | | NRHS |
| 9519 | TTAX | Trailer Train Co. (flush deck flat cars equipped with foldaway container pedestals, knock-down hitches and bridge plates; for transporting trailers or containers or combinations of both) | Jan-75 | | NRHS |
| 9520 | TTAX | Trailer Train Co. (flush deck flat cars equipped with foldaway container pedestals, hitches and bridge plates; for transporting trailers or containers or combinations of both) | Jan-80 | | NRHS |
| 9521 | TTAX | Trailer Train Co. | eliminated 1/92 | | NRHS |
| 9522 | TTAX | TTX Co. | added 1/92 | | NRHS |
| 9523 | TTAX | TTX Co. (skeletonized, 5-unit, articulated all-purpose car for use between lift on/lift off facilities only, capable of carrying various combinations of trailers and/or containers of various lengths and widths) | 1/94-7/2000 | | NRHS |
| 9524 | TTAX | TTX COMPANY {TRAILER TRAIN COMPANY} | | | PWRC |
| 9525 | TTAX | Trailer Train (TTX Corporation) | | | RSRV |
| 9526 | TTAX | TTX COMPANY | | | SCAC4 |
| 9527 | TTB | Aerolineas Turisticas Del Caribe, S.A. de C.V. | Callsign: Aero Turisticas, | MEX | AVCODES |
| 9528 | TTB | Aerolineas Turisticas del Caribe | | | ICAO1 |
| 9529 | TTBA | TOMKEN TRANSPORTATION (BROKERAGE DI | | | SCAC4 |
| 9530 | TTBB | TRI-CONTINENTAL TRUCK BROKERAGE INC | | | SCAC4 |
| 9531 | TTBE | TETI BAKERY INC | | | SCAC4 |
| 9532 | TTBF | TEPA TRUCKING | | | SCAC4 |
| 9533 | TTBG | TTT BROKERAGE LLC | | | SCAC4 |
| 9534 | TTBH | TRANSPORTES TRR SA DE CV | | | SCAC4 |
| 9535 | TTBI | TRANSPORT BOUTET INC | | | SCAC4 |
| 9536 | TTBK | TRIPLE T TRUCK BROKERS INC | | | SCAC4 |
| 9537 | TTBL | T T BAIT LIMITED | | | SCAC4 |
| 9538 | TTBO | TRANSPORT TRANSBO INC | | | SCAC4 |
| 9539 | TTBP | TRINIDAD AND TOBAGO PETROLEUM | | | SCAC1 |
| 9540 | TTBR | TRANSPORTES BARRERA | | | SCAC4 |
| 9541 | TTBS | TANNER TRUCKING & BIT SERVICE LTD | | | SCAC4 |
| 9542 | TTBT | TEDS TRUCK BODY & TRAILER SERVICE I | | | SCAC4 |
| 9543 | TTBU | EQUIPPED4U BV | | NL | BIC |
| 9544 | TTBV | TC TRANSPORT INC | | | SCAC4 |
| 9545 | TTBW | TOMITAS TRUCKING INC | | | SCAC4 |
| 9546 | TTBX | Trailer Train Co. | added 4/1968; 10/1968-1/1980; eliminated 1/1992 | | NAKINA |
| 9547 | TTBX | TTX Co. | added 1/1992; 1/1994-7/2005 | | NAKINA |
| 9548 | TTBX | Trailer Train Co. | added 4/1968 | | NAKINA |
| 9549 | TTBX | Trailer Train Co. (89'3"" and over FA flats equipped with bi-level automobile carrying superstructures furnished by member railroads. Cars are not equipped with hitches and bridge plates. Equipped with hydraulic draft gear) | 10/1968 | | NAKINA |
| 9550 | TTBX | Trailer Train Co. (flat cars, length 89'4"" or over, equipped with bi-level auto racks furnished by member railroads) | 4/1970 | | NAKINA |
| 9551 | TTBX | Trailer Train Co./TTX Co. (flat cars equipped with bi-level auto racks furnished by participant railroads) | 1/1975-7/2000 | | NAKINA |
| 9552 | TTBX | Trailer Train Co. | added 4/68 | | NRHS |
| 9553 | TTBX | Trailer Train Co. (89'3" and over FA flats equipped with bi-level automobile carrying superstructures furnished by member railroads. Cars are not equipped with hitches and bridge plates. Equipped with hydraulic draft gear) | Oct-68 | | NRHS |
| 9554 | TTBX | Trailer Train Co. | Apr-70 | | NRHS |
| 9555 | TTBX | Trailer Train Co. (flat cars equipped with bi-level auto racks furnished by participant railroads) | 1/75-1/80; eliminated 1/92 | | NRHS |
| 9556 | TTBX | TTX Co. (flat cars equipped with bi-level auto racks furnished by participant railroads) | added 1/92; 1/94-7/2000 | | NRHS |
| 9557 | TTBX | TTX COMPANY {TRAILER TRAIN COMPANY} | | | PWRC |
| 9558 | TTBX | Trailer Train (TTX Corporation) | | | RSRV |
| 9559 | TTBX | TTX COMPANY | | | SCAC4 |
| 9560 | TTC | Transteco | Callsign: Transteco, | ANG | AVCODES |
| 9561 | TTC | Transteco | | | ICAO1 |
| 9562 | TTC | AAR-TRANSPORTATION TEST CENTER | | | PWRC |
| 9563 | TTC | The Train Company (RailInsight B.V.) | | NL | TRAFFIC |
| 9564 | TTC | The Train Company | | NL | VKM |
| 9565 | TTCC | TERMINAL TRUCKING COMPANY, INC | | | SCAC1 |
| 9566 | TTCF | TOTAL TRANSPORTATION CONCEPT INC | | | SCAC4 |
| 9567 | TTCG | TRANSPORTES DE CARGA GERSHEL S A DE | | | SCAC4 |
| 9568 | TTCI | TRANSPORTES CISNEROS | | | SCAC4 |
| 9569 | TTCM | TRANSPORT TRICAM INC | | | SCAC4 |
| 9570 | TTCM | The Transport Company (Milwaukee) | City: Milwaukee | USA | TRAFFIC |
| 9571 | TTCNG | T.T. CARGO mednarodni prevozi d.o.o. | | SI | VKM |
| 9572 | TTCQ | TREAT CORE SUPPLY | | | SCAC4 |
| 9573 | TTCS | TRANTEC SYSTEMS INC | | | SCAC4 |
| 9574 | TTCU | TNC CHEMICALS CO. | | | PWRC |
| 9575 | TTCU | TNC Chemicals | | | RSRV |
| 9576 | TTCV | T & T CARGO SERVICES INC | | | SCAC4 |
| 9577 | TTCW | TRIMAC TRANSPORTATION CENTRAL INC | | | SCAC4 |
| 9578 | TTCX | Texas Chemical Co. | 8/1920-7/1935 | | NAKINA |
| 9579 | TTCX | Consolidated Chemical Industries Inc. | 7/1937-4/1938 | | NAKINA |
| 9580 | TTCX | Tulsa Tank Car Corp. | 1/1945 | | NAKINA |
| 9581 | TTCX | The Thomas Co. | added 10/1954; eliminated 10/1955 | | NAKINA |
| 9582 | TTCX | Trailer Train Co. | 4/1970-1/1980; eliminated 1/1992 | | NAKINA |
| 9583 | TTCX | TTX Co. | added 1/1992; 1/1994-7/2005 | | NAKINA |
| 9584 | TTCX | Trailer Train Co. (flush deck flat cars equipped with movable foldaway container pedestals for transporting containers) | 4/1970-7/1985 | | NAKINA |
| 9585 | TTCX | Trailer Train Co. (60', 89'1"" and 89'4"" COFC cars. 60' cars (5 digit car numbers) are equipped with fixed container pedestals and limited cushioning and are stencilled 'DO NOT HUMP'. 60' cars are capable of carrying 3-20' or 1-40' & 1-20' container fully loaded to a maximum gross weight per car (containers & lading) of 159,000 lbs. 89'4"" cars (6 digit car numbers beginning with '9') are equipped with movable foldaway container pedestals capable of carrying various combinations of containers of varying le | 10/1991 | | NAKINA |
| 9586 | TTCX | TTX Co. (60', 89'1"" and 89'4"" COFC cars. 60' cars (5 digit car numbers) are equipped with fixed container pedestals and are capable of carrying 3-20' or 1-40' & 1-20' container fully loaded to a maximum gross weight per car (containers & lading) of 159,000 lbs. 89'4"" cars (6 digit car numbers beginning with '9') are equipped with movable foldaway container pedestals capable of carrying various combinations of containers of varying lengths loaded to a maximum gross weight per car (containers & lading) of | 1/1992-7/2000 | | NAKINA |
| 9587 | TTCX | Texas Chemical Co. (Consolidated Chemical Industries Inc.) | Apr-38 | | NRHS |
| 9588 | TTCX | Trailer Train Co. | Apr-70 | | NRHS |
| 9589 | TTCX | Trailer Train Co. (flush deck flat cars equipped with movable foldaway container pedestals for transporting containers) | 1/75-1/80 | | NRHS |
| 9590 | TTCX | Trailer Train Co. | eliminated 1/92 | | NRHS |
| 9591 | TTCX | TTX Co. | added 1/92 | | NRHS |
| 9592 | TTCX | TTX Co. (60', 89'1" and 89'4" COFC cars. 60' cars (5 digit car numbers) are equipped with fixed container pedestals and are capable of carrying 3-20' or 1-40' & 1-20' container fully loaded to a maximum gross weight per car (containers & lading) of 159,000 lbs. 89'4" cars (6 digit car numbers beginning with 9) are equipped with movable foldaway container pedestals capable of carrying various combinations of containers of varying lengths loaded to a maximum gross weight per car (containers & lading) of 150,0 | 1/94-7/2000 | | NRHS |
| 9593 | TTCX | *CONSOLIDATED CHEMICAL INDUSTRIES, INC [TEXAS CHEMICAL CO.] | | | PWRC |
| 9594 | TTCX | *TULSA TANK CAR CORP. | | | PWRC |
| 9595 | TTCX | *THE THOMAS CO. | | | PWRC |
| 9596 | TTCX | +TTX COMPANY {TRAILER TRAIN COMPANY} | | | PWRC |
| 9597 | TTCX | Trailer Train (TTX Corporation) | | | RSRV |
| 9598 | TTCX | TTX COMPANY | | | SCAC4 |
| 9599 | TTCY | TITAN COMPANY, THE | | | SCAC4 |
| 9600 | TTCZ | FLEXI-VAN LEASING INC | | | SCAC4 |
