Btw, forgot to update this. I noticed some pinging under partial throttle and a load (exactly where matt said he would expect it), so i switched back to 91 before goin on a weekend camping trip. Im glad i caught it before i left. I know for a fact that it wasnt there for the first half tank of 87 but maybe the drastic drop in the temp here leaned it out. C'est la vie.
Also, took the truck down talimena scenic drive, the first time since i changed from drop springs and shackles to a 3/4 drop and this thing loves those long fast corners. Doing 80 in a marked 35mph turn was a breeze