Spare tire

Had a quick question, if i'm running 285/75/16 ridge grapplers will there be any issue on diffs if run a 255/85/16 different tire as a spare? overall diameter is pretty much the same and i'm wondering if that is the main factor here. i guess i could always just make sure the 255 is in the front if i did get a flat, but just wanted to see what you guys think

 

Had pretty much the same question myself a couple months ago (I'm running the 255s but my spare at the time was a 265/75/16).....long story short, it's better to have a same-diameter spare if you can help it, but if it'll just be for a short distance then you'll be fine since these trucks have open diffs. Since both your tires are 33" you're good to go.

https://www.tacomaworld.com/threads/mismatched-spare-issues.598742/