Both for reference and for the fun of it, I am posting the sizes of the "standard" steel wheels for most common IHC tractor models. Some models had over a dozen options for different types and sizes of steel wheels, but these "standard" were the most common. They are the flat surface rear steel wheels with 4", 5", or 6" spade lugs except for the Fairway which had spike lugs.
W12 / W14 22 1/2 x 3 front, 42 x 8 rear; Fairway 12 24 x 8 front, 40 x 16 rear; 10-20 30 x 4 1/2 front, 42 x 12 rear; 15-30 / W30 30 x 4 1/2 front, 42 x 12 rear; W40 34 x 6 front, 50 x 12 rear; F12 / F14 22 3/8 x 4 front, 54 x 6 rear; Regular / F20 25 x 4 front, 40 x 6 rear; F30 25 x 4 front, 42 x 12 rear; FH 22 1/2 x 3 1/2 front, 51 x 6 rear; FM 22 1/2 x 4 front, 51 x 8 rear; W4 22 1/2 x 3 1/2 front, 40 x 8 rear; W6 22 1/2 x 4 front, 42 x 10 rear; W9 30 x 6 front, 48 x 12 rear; WR9 34 x 6 front, 54 x 12 rear; F300 - F460 22 1/2 x 3 1/2 front, 51 x 6 rear; F400 - F560 22 1/2 x 4 front, 51 x 9 rear; W600 / W650 30 x 6 or 34 x 6 front, 48 x 12 or 54 x 12 rear; I560 & I660 54 x 12 rear; F706 & F806 54 x 12 rear.
The Farmall 706 and Farmall 806 were the last IHC tractor model with steel wheels listed as an option. Rubber tires were the standard on all IHC tractor models starting in 1938 and 1939. However, after the war started, steel wheels again became the standard wheels on most IHC tractors untill 1946 when rubber again became the standard.
Harold H
W12 / W14 22 1/2 x 3 front, 42 x 8 rear; Fairway 12 24 x 8 front, 40 x 16 rear; 10-20 30 x 4 1/2 front, 42 x 12 rear; 15-30 / W30 30 x 4 1/2 front, 42 x 12 rear; W40 34 x 6 front, 50 x 12 rear; F12 / F14 22 3/8 x 4 front, 54 x 6 rear; Regular / F20 25 x 4 front, 40 x 6 rear; F30 25 x 4 front, 42 x 12 rear; FH 22 1/2 x 3 1/2 front, 51 x 6 rear; FM 22 1/2 x 4 front, 51 x 8 rear; W4 22 1/2 x 3 1/2 front, 40 x 8 rear; W6 22 1/2 x 4 front, 42 x 10 rear; W9 30 x 6 front, 48 x 12 rear; WR9 34 x 6 front, 54 x 12 rear; F300 - F460 22 1/2 x 3 1/2 front, 51 x 6 rear; F400 - F560 22 1/2 x 4 front, 51 x 9 rear; W600 / W650 30 x 6 or 34 x 6 front, 48 x 12 or 54 x 12 rear; I560 & I660 54 x 12 rear; F706 & F806 54 x 12 rear.
The Farmall 706 and Farmall 806 were the last IHC tractor model with steel wheels listed as an option. Rubber tires were the standard on all IHC tractor models starting in 1938 and 1939. However, after the war started, steel wheels again became the standard wheels on most IHC tractors untill 1946 when rubber again became the standard.
Harold H