whats the biggest tire you can fit on a stock 1999 ford ranger?

 

2wd or 4wd ?
I believe you have a slight more clearance on a 4wd, but not sure.
I have 255-70-15's on my 2wd ranger, slightly lowered, and had a rubbing issue when turning sharply. but I changed tire brands (same size) and now they dont rub, so brand of tire can play a role.

 

Bone stock you can clear 265/75R16's

 

https://www.ranger-forums.com/f38/ch...re-size-20047/