I had the spare tire out today to check air pressure and measured the spare area for a larger tire. It’s ~ 35 inches front to rear from the suspension crossmember heat shield to the trailer hitch. It’s also ~ 35 inches side to side from exhaust shield to exhaust shield. I think the issue will be tire width, the factory spare already hangs down below the hitch. I have a 2021 high country suburban with 285/50r22 Toyo at3’s on stock wheels, the factory spare is 265/70r17. I am thinking something like a 255/80r17 may be the best bet for matching my existing tire diameter and not being so wide it hangs down and catches on stuff.