I started working on my 18-28 this last month and today when I started to flush and clean the rear end transmission I found a major problem: the housing has two large cracks in it. It appears to have gotten water in it at some point in its life and pushed a piece of the inside wall out and has a 10 inch long crack in the bottom. It does not show signs of anything hitting it from some thing coming apart that is why I think water must have froze in it. I guess I will start searching for a housing. If anybody knows of any of these tractors being parted out or an 80 standard with the 3 speed trans please let me know.