the axle has a big gear on the inner end of it, held on with a large nut. So you have to remove the axle housing assembly from the side of the transmission, then remove nut, remove the axle seal and then under the seal is a circlip. Remove the clip and then the axle. Remove bearing from axle if it's not already off, install it into the housing, put the clip in and then the new seal. Slide the housing down over the axle, reinstall bearing, gear, nut. Clean all the liquid gasket off of the housing and the transmission, and apply new stuff (I use ultra gray) Reassemble the housing assembly to the transmission.
you will have to drain all the trans fluid out. Also one thing I do after the repair is made is to paint the liquid gasket with the correct gray paint.
The housing assembly is heavy so be prepared. Also when removing it, if you have the tractor supported in the center, the tractor may want to tip to the opposite side. I always used the front end loader, bucket on the ground and level, to help keep it from tipping. Floor jack or overhead crane to support/ remove the axle housing (I forget it's weight but it's pretty heavy). Easiest to remove the fender depending on which side it's on. Getting the wheel/tire off and then supporting the housing is the worst part of the whole job--if the tire is filled you're in for a treat.
