The 2003 ford ranger lug nuts are thread size: 1/2"-20, hex size: 20.6 mm. when you are adding or removing the lug nuts from a car then you will want to be careful not to damage them. if you overtighten them then you run the risk of snapping them or stripping them, especially if they are old or rusted. if you strip the lug nuts then they will simply spin in the socket and you won't be able to get them loose. if that happens then you will need a mechanical press to push them out, but this can damage the wheel. if you snap the bolts then you will need to remove the rotor on the wheel and unthread them from the back. both of these are simple enough to avoid if you take some caution.
The 2003 ford ranger lug nuts are thread size: 1/2" x 20. hex size: 3/4". overall length: 1.375".