Since you have a 3rd gen 4runner, i think that 265/70/16 is a good size. I had both 265/75 and 265/70 on my '02 4runner (3rd gen like yours). For the engine power, 265/70 felt perfect. The 265/75 size had a significant effect on my 4runner's highway and acceleration performance. It is all relative...you may not care for the slower performance with the bigger tires. The way i figured was that the 4runner (3rd gen) had pretty good clearance already, so i went with the smaller size to keep stock performance and stock fuel economy. (Remember, going with an off-road tire in stock size already knocks your fuel economy and performance...so, going with a bigger off-road tire will punish you more.)
For the 4th gen 4runner, this tire size issue is less significant because of the increased engine power.
Hope this helps.
