truck wont accelerate

I cannot see the car so only your discription of the problem. I could answer this question yet a lot of things can cause the problem. My first look would be to the cat. By chance she has pluged. This will cause back pressure and the lack of acceleration.

this could also be the intake, the intake in the older rams have been know to go out i had mine go out about a year ago, : way to tell if it is your intake is start your truck pop your hood and listen to see if it sounds like it is sucking air, this just means that one of your intake seals has broken and needs to be replaced.