Dead Battery
 

Truck barely runs dash lights, and doesn't fire.

I replace both batteries with Die Hard Platinum's, and truck starts with a bunch of extra pepp. . . . ! My test drive was not as noticable.

My question is if removing both of my batteries reset anything with my FICM programs. I was running 80hp tune, which I love, and the truck felt less potent after putting in new batteries. Is that just in my head???:notallthere:

Removing batteries would not have an effect on your FICM tune. Your truck is probably going through a relearning cycle to adapt to you and your driving. When the batteries are disconnected the "RAM" is lossed and the computer has a bit of a learning curve to go through.