Why does my tie rod have a different thread than the parts I can get at the parts store for my 1986 Dodge Ramcharger

The shaft on the drivers side tie rod end has coarse thread and everything at the part store has fine thread

My car has 120000 miles.
My car has an automatic transmission.

– Why does my tie rod have a different thread than the parts I can get at the parts store for my 1986 Dodge Ramcharger