brock2280

i have a 2002 explorer with the 5r55w tranny in it. when i started it up one morning and went to put it in reverse nothing happened. the same with drive and all other gears. i had read it might be my solenoid block or pack. so i replaced that along with the filter and also put mercor v fluid in it. still has the same issues. the linkage and torque converter look to be fine. i believe it has to be something electrical and not a band or somehting because the truck ran fine a couple hours earlier that same day it messed up. can anyone give me any advice on this, it would be really appreciated. thanks