I own two 19.5 Airens 42 inch mowers. We mow aprox. 2 acres around once a week. Just before the two year warranty lapsed on the mowers, I saw that the axel seals on the two mowers leaking right and left. I called the dealer and he said they were not serviceable and an Airens rep. would have to look at them .I took them to their shop and waited. The rep. agreed that they would replace the transmissions on the two mowers as the seals were not serviceable. So the mowers got new transmissions, and I'm back mowing. Just over two years after that I again saw one of the mowers was leaking, warranty gone now I could not believe I was going to have to spend six hundred bucks plus labor to fix this mower. I did a lot of research and could not find one fix for this. So after much though I decided to try my own fix .I drilled a filler hole in the top of the case checked the fluid level and guessed it had lost about 6oz. of fluid. I used a syringe to inject some form a gasket around the axel seal and so far so good (six months ) no leaks. I didn't have to drop the transmission either. I can also redo it if I need to . Non serviceable dose not always apply.