I requested and received my build sheet on my jeep a few days ago and this his been bugging me. It says i have a 19 gal gas tank, but when i fill up when the gas light comes on down about halfway in the red i can only put at most 12 gal in. Did they make a mistake on the size or am i missing something? I'm the 3rd owner my dad had it before me,but is there a chance the original owner changed tanks to a smaller one? What benefit is that, besides less $at the pump? What do y'all think?