Does anyone know the size of a rear lug nut on a 5660SUHD? My set goes up to 21MM but I want to buy just one not a whole oversized set. Called dealership parts dept and they did not know.
So you’re referring to the hex size so you can buy a socket? In US 7/8” is an almost perfect 22mm, 15/16” fits a 24 mm tightly. If you don’t have those, measure it… choose your weapon below.
I would just go into the dealer's parts department and buy one lug nut that is specifically for your tractor. You will have a spare should you ever lose your nut, and be able to get the correct size to use on your nuts.
Your front and rear lug nuts may be different sizes - mine are. In those sizes fractional inch sockets usually fit well, too. I prefer six point sockets for that purpose.