How to fill your rear tires:
Step 1, buy the fill/burp valve. Available at tractor supply, Gemplers,
Amazon and other places. Look up the 75% fluid fill for your tire and set out just that amount of fluid.
Step 2: Get a 5 gallon bucket, some short pieces of garden hose and a small pump. I used the $8
drill pump from Home Depot. it is crap but will last for this job.
Step 3: Make sure the valve stem is at 12 o'clock. Jack up one side of tractor so that tires is just barely sitting on the ground. Not free to spin but almost no weight on it. The reason for this is so the tire bead will not be broken when we let most of the air out of tire.
Step 4. hook up pump and pour your liquid in the 5 gallon bucket and dump in the inlet hose , hook up drill pump and fill valve, and get your valve stem removal tool ready.
Step 5: remove valve stem core, let most of the air out but not all. Hold thumb over hole to retain some air pressure while screwing on the fill adaptor. I also put a simple garden hose on/off ball valve in line with the adaptor to make it easier to control the loss of air pressure after getting the fill valve on. So to recap, I put the fill adapter on immediately after removing the valve stem core. Then let most but not all of the air out with my inline ball valve. The reason for leaving some air in is to prevent the bead from unseating on the rim. Also see step 3 above.
Step 6, Start the drill pump and start pumping in the fluid. As the fluid goes in the air pressure remaining in the tire will increase. The will build up a "head pressure" the pump will not be able to overcome, and the pump will labor and the fluid transfer rate will go down. Time to stop and burp some more air out of the tire using the little burp button included on the fill adapter. Let some air out, not all.
Step 7: Pump in some more fluid. With the little junky drill pump, I had to stop and burp at about every 3 gallons of fluid. Just use common sense. Pump burp, pump, burp until the measured amount of fluid for 75% fill is pumped into the tire.
Step 8. Get valve core ready, and remove fill adaptor and get core screwed back in and air up tire to your manuals normal air pressure. Mine is at 20 lbs.
Step 9: Let down jack and repeat procedure for other tire.
Step 10: Enjoy increased traction and stability.