1951 L150... What diff do i have?

Scottso... I just checked my parts manual. The parts are numbered different in the diagrams, but when I compared them, the IH part numbers for 45, 23, and 21 all match up exactly. It looks like i may have a chance to get 4.30 gears.

Scott,
I had one rear axle come in where they had tried to change the ratio without changeing the case, the ring gear would and did bolt up but the gear was in the wrong place for the new pinion, as is too often, they "forced" it i place and distroyed the diff and axle houseing.

It is why you need to do (as you did) look and see what number is called for, it has to do with where the flange (where th ring gear bolts to) is placed on the case, faster ratios are further to one side the slower.

I think where I went wrong is one time when I fipped back, I was on PAGE 14-3 not FIG 14-3. Sorry that I ever doubted you!