Honestly, if you want to be doing this right, you really need to be measuring from the ground to the top edge of the tire where the sidewall turns and becomes the tread - NOT to the highest point of the tire which will be the center of the tread. Or, you could measure from the ground to the center of the wheel and then X2. This is after all what you would need to calibrate your speedometer.
Having said that, my 40" Nitto K-Spec Trail Grapplers measure 38" and were most likely closer to 38.25" new. My 37" Nitto Trail Grapplers measure 35" now but have quite a few miles on them. If I could guess, they came in closer to 35.5" new. Same could be said of the Toyo MT's that I ran in both these sizes. My 285/70R17's Nitto Trail Grapplers measure about 32". The 35" Goodyear MT/R's with Kevlar I ran only came in at about 33" and at last check, the old Cooper STT's I had only came in at about 30.5" but would guess they were more like 31" new.
I could go on and on with all the tires I have tested but, I think you can see the pattern. NO tire will have an actual measurement that equals what is listed on the sidewall and most will come in at about 2" less than what is advertised - at least, if you measure it like you should. This is why I always say that actual measurement should only be taken into consideration when calibrating your speedometer and NOT when talking about things like lift. When talking about things like how much lift is needed to clear a tire, you should always refer to what is written on the sidewall as that is what manufacturers are working off of - NOT actual measurement.
