Not your normal tire size question

question couldn't find the answer. And I know the obvious jokes. But how much does size matter? Would a 275 70 16 tire vs. A 255 85 16 tire be much of a performance difference here in the desert. Going over boulders etc. They are 31.5" vs 33". Is that a drastic difference? Is the additional ground clearance that big of a deal. Or what?

 

I would go 265/75R16 over the 275s.

Depends on what you are looking for, 1.5" = 0.75" ground clearance difference. That is really not much. If your truck is a daily driver, smaller and lighter tires will have less effect on MPGs and power. If it is strictly a rock crawling weekend warrior, maximum ground clearance may be more important.

Going larger than 32s often requires trimming/cutting of the truck.

 

You would do the 265 over the 255/85/r16 as well?

 

I'm running 265/70R17 which is the same as 265/75R16. My truck is a daily driver with a few multi-day off road trips a year. I care about mpgs and power and performance, all of which 33s will reduce. I didn't want tires so large I would have to cut off my cab mount, weld new box ends and trim my truck to make them fit like you usually have to do with 33s. Not worth hacking the truck and the performance sacrifices for 0.75" ground clearance gain in my case. I've not been on a trail where I couldn't make it but if I had 0.75" more clearance I could. Armor would be a better investment at that point IMO anyway. For my use, the 265s and a more moderate build make way more sense. All depends on your use and what makes sense to you.

Here is my truck with a 2" front lift, 1.5" rear lift on 265/70R17s compared to stock:
https://www.tacomaworld.com/threads/baja-tx-pro-kit-icon-aal.385619/page-2#post-10688141