can someone please explain what this stands for and what it does and the relation to mpg?

 

Powertrain
Control
Module

controls your truck

 

i saw some where on here a few days ago someone was having problems with really bad mpg's and they took it to the dealer and they did a PCM update and it gave them better gas mileage dont know if its BS or not but it might be something to look into i am going to the next day i have off of work

 

sweet maybe u can update ur findings

 

yea thats me. and yea youll get a little bit better mileage