I just bought a JD4120 w/ FEL, R4 tires and have a couple of days to choose whether to fill the tires.
The choices I know of include:
FILLING TIRES - Calcium Chloride, Rim Guard, or water/non-toxic antifreeze
WHEEL WEIGHTS
3-POINT WEIGHT
REAR IMPLEMENT
My property has 4 acres of messy clear...