33” / 285s & getting 25 MPG highway average…

Those with upgraded size tires, I suggest you take a long trip and compare Google maps' distance to what your odometer indicates.

I'm on Toyos 35s and my odometer showed 74.5mi while Google maps said 84mi. This is the most accurate measurement. Which makes my odometer understated by almost 13%. My speedometer is only off by 10%. 80mph will show 88mph on Google Maps GPS.

Even a stock Tacoma it is likely off by 1-3%
Toyos 35/12.5/17 only measured around 33.75" mounted.

285/70/17 calculates to 32.7" and likely measures sub 32.5" mounted.

I've researched this thoroughly thru many threads on many forums. 37s measures sub 36". Most 35s 33.5-34".

 

Easier (and more accurate) to use a quality GPS vs odometer over longer distances for comparison.