Present TTX Car Classification System

The following car classification was adopted in 1968 and took until 1974 to be completely adopted. It consists of six characters.

Character: 1 2 3 4 5 6
Example: T W G 5 0 P

 

Interpretation (partial listing)
Character: Meaning: Examples:
1  Car Builder

A = American Car & Foundry (ACF)
B = Bethlehem Steel
C = Pacific Car & Foundry
D = Difco
F = FMC Marine & Rail
G = Gunderson, Greenbrier
J = Johnstown America and Freight Car America
N = National Steel Car
P = Pullman-Standard
R = Trinity Industries
T = Thrall Manufacturing
U = United American Car
W = Berwick Forge & Fabricating
Y = Hyundai

2 Deck Height D = Depressed-center flatcar
L = Low level (less than 39 inches)
S = Standard level (39 inches or higher)
Other A = All-purpose
M = Integrated Multi-level car and superstructure
R = Auto rack superstructure
T = RoadRailer bogie
W = Double-stack well car
3 Draft Gear F = M901 or M901E friction draft gear
G = M901G high-capacity friction draft gear
H = Hydraulic end-of-car cushioning
Other A = All-purpose
B = Bi-level rack or multi-level car
T = Tri-level rack or multi-level car
U = Uni-level rack or multi-level car
4, 5  Design No. For 89-foot Standard-Level Flatcars:
10 to 19 = Cars with draft pockets for friction draft gear or specific hydraulic cushioning unit
20 & up = Cars with universal draft pockets
80 = Cars with 39-1/2-inch high deck and wider side sills
90 = Older flush-deck car converted to all-purpose with universal draft pockets
For 89-foot Low-Level Flatcars:
10 to 19 = Flatcar 60-feet over end sills
20 & up = Flush-deck car body with universal draft pockets
For 60- to 73-foot Standard-Level Flatcars:
60 to 62 = Flatcar 60-feet over end sills
64 = Center beam car 64-feet over end sills and 60-foot inside length
71 to 73 = Flatcar 68-feet over end sills with or without end bulkheads
74 = 73-feet inside length center beam car with plate web center beam structure
75 = 73-feet inside length center beam car with diagonal truss center beam structure and 263,000-pounds gross rail load
76 = 73-feet inside length center beam car with diagonal truss center beam structure and 286,000-pounds gross rail load
For Heavy-Duty Flatcars:
Design number = Usable length of loading deck
For Multi-level Cars and Auto Rack Superstructures:
One-digit numbers = Auto rack superstructures
Two-digit numbers = Complete multi-level cars
For Multiple-Unit Cars:
2n = Two-unit cars
3n = Three-unit cars
4n = Four-unit cars
5n = Five-unit cars
Second digit may or may not have a specific meaning

For Articulated Double-Stack Cars:
50 = Cars with 100-ton articulated trucks
51 = Prototype cars built with 100-ton articulated trucks and converted to 125-ton trucks
52 = Cars with 125-ton articulated trucks
53 = (23) 100-ton cars acquired used from APL
53 = Cars with 125-ton trucks and having 53-foot wells

For All-Purpose Spine Cars:
30 = Three-unit 57-foot TTRX car
33 = Three-unit 53-foot TTAX car
53 = Five-unit 53-foot TTAX car
55 = Five-unit 48-foot TTAX car
6  Subclass, if any A = All-purpose
C = Equipped for COFC service
M = Modified from originak construction of car
P = Protoype car

 

Original Trailer Train Classification System

Cars were assigned classes based on the length of the loading deck.

Character: 1 2 3 4 5 6
Example: F 8 9 C H W

 

 

Interpretation (partial listing)
Character: Meaning: Examples:
1 Type of Car

F = Flatcar
G = TOFC car built by GATX

2, 3 Length Length in feet
4 Subclass, if any  
6 Various F = Equipped for auto frame service
M = Modified from original construction of car
P = Equipped to carry pipe
W = Underframe widened for Wide-body auto rack