Any 3rd gen truck or 2nd gen Runner that came w/factory 31's and a 5-spd had the 4.56 gears. My sister's 95 Runner w/3.0 and auto had the 4.56's, and stock tires, though I am not sure what year Toyota started this, or if it was limited to Runners only.
You will need to look for the gear code on the door plate, which is located in the lower right corner(sticker's lower right corner), to the right of the bar code, and above the "In" in "Made In Japan". The code for 4.56 gear ration is G254. The G is for the 8" diff, the 25 is for the 4.56 gears, and the 4 is for the # of pinions.