Honda says to only use Honda HST fluid; there is no Honda-approved alternate fluid. The total capacity of the hydrostatic transmission on the Honda H2013 is 3.3 quarts. Always check/fill the HST fluid level when the tractor is parked on a level surface. Don't just pour 3.3 quarts in, but add HST fluid until you can see the level rise above the MINIMUM but remain below the MAXIMUM marks on the tank.
Genuine Honda HST fluid is available in a 12 ounce bottle, Honda Part Number 08208-HST02, list price $5.98.
Google any part number to find a Honda Dealer selling it online, or use this link to find a Honda Dealer in your area: Find A Honda Dealer
