I get the same thing when I say I have 35s.Not doubting you but you must have seen them. I deal with people ALOT who act like they know what they are talking about but they don't. Metric tire sizes only go to about 315/325 range witch is 12.50 to 13 wide and 70 or 60 aspect ratio to get from 34.5 up to the max of 35.6 tall. After that for the most part it goes to 37, 38, 40, 42, etc. So I guess my point about you seeing them, in person, is because, unless you have physically seen the size on the side of the tire, you would be guessing and just looking at a tire and wheel and saying that is a 37 is not that easy. I tell people all the time my F150 has 35's they call me a liar even after they look at the truck so I say "Read the sidewall" ...……. "but they don't look like 35's". correct because they are 35's and on 20's NOT on 17's. They "look" like 33's because the rims are 20's. I remember here someone posted three wheels and tires leaning on the wall and asked to guess what size they were . they "looked" to me like a 32/33 and a 35. but here again I see it everyday. I work in a 4X4 shop. Have had a lot of TJ's in the shop lately and it is weird to see so many 33's on 15. makes me think they are 35's on 17's just by the way they "look".
Sorry if I seem like I am rambling I guess my point would be did you see them or are just "looking" at them and going with the 37's ???
Not that I don't believe you because I think it is going to be awesome if they are 37's and we already know this Bronco is going to be a badass.
Also rollin on 20s.