21OS111743, the number
1 after the letter
S is the Letter
I = eye.
21OS-I-11743
21 - Assemply Plant , Janesville, WI
OS - 1946 Model Year
OS - (interim) = 1st series Design, (PK is the 2nd series Design)
OS - 4400 Series Model
OS - 160 inches Wheelbase
OS - 1.5 = 1 1/2 ton
I - September, Month truck was Assembled
A = Jan.
B = Feb.
C = Mar.
D = April
E = May
F = June
G = July
H = Aug
I = Sept. Your truck
J = Oct.
K = Nov.
L = Dec.
11743 - Number of that model of truck Assembled at the Janesville, WI plant, Starting at 1001.
Your truck was the 10,742nd truck to roll off the assembly line.
Source>
1946 TRUCK MODEL SERIAL IDENTIFICATION
