throttle response

I have a 2013 double cab 4wd, stock 4.0L, AT, 3" leveling lift with 285/16/75 tires. I have noticed at times that the acceleration is sluggish. It will be like that all day, then the next day it runs great. I have noticed that during this time there is a little bit more play in the accelerator pedal before the engine responds. I plan on addressing this with the dealer but I was wondering if anyone has any ideas before I go.
Thanks,
Ron

 

Its drive by wire no throttle cable so most are going to claim something about "no response" or some deal I usually skip over when I read. my guess is goin to be that the days it drives better its less humid or cooler air outside and if truck reacting better is just causing u to think if pedal feels different. if all else fails... boost it till it drives like u want it to.