There is a performance mod that can be done to the
ecu but it requires you to send it out and have it calibrated
to your tire size, weight, upgrades, performance needs and driving type.
https://www.4x4parts.com/nissan/computer-upgrade-p-5542.htmlits from 4x4parts.com and its 200+ and you lose your truck for however long. the v-plus module they offer doesnt reset the ecu but allows you to monitor the different variables and adjust your driving is what im told.
reseting or flashing the ECU is something im not familiar with but i know the Xterra ECU sucks to try to work on yourself or lots of guys would be adjusting for tire size, gears etc.... if you guys figure a way to change things without messing everything up - you just may be on to something big. Do it for less than 200 and without me losing my truck for 2 weeks and im in.