What size rim would i need if i have a 98 4dr lt blazer with 31x10.50 tires

 

that doesn't help us a whole lot. you could have an array of rim sizes with that same tire. you need 3 sizes to describe your tire, tire diameter, tread width, and rim size.

if youre still using the stock rims theyre 15x7s, with a 5x4.75 bolt pattern. If you have yet to buy the tires yet, then you just gotta pick what size rim you wanna go with, then find the 31x10.5s to fit your new rim size.