My truck build is on the lift right now so can't give you an exact measurement. But can provide this feedback. I initially set mine to the ride height shown in the manual. But with full fenders on my build, the tires were too close to the fender lips and I was afraid they would rub under normal driving. So raised ride height all around about one inch. Still might be a little low, but going to start there. At that ride height, the grille bottom at the front is clearly the lowest part of the entire underside. It's just under three inches. Close and I'll need to keep an eye one it. Fortunately, speed bumps aren't too much of a thing around where I live. But I don't think I'd want it any lower.