NO power stock?

[outlaw6oh]

When the truck is stock I have no power as in the truck don't move, in Park and Neutral it slowly runs up the rpms' but when you put it in gear it just sits there. I have no codes, kinda seems like a dead pedal but the truck seems to run fine tuned. I do have access to a scanner but the person who has it doesn't deal with 6.0s and has never scanned one so we don't know what to look for, what would I be looking for to find the problem?

Thanks, Brian