Farmall Cub

whats the differenc between 21 & 24 teeth count on the steering? is it that the older model had 21 & the newer models had 24? will the worm gear fit both 21 & 24 ??

Harryo The 21 tooth gear was used on tractors serial number 221871 & below. The 24 tooth gear was used serial number 221872 & up. The serial number break on lo-boys was at 16775 / 16776. They require different worm shafts.