weak air from vents-lots of noise behind dash
 

I have an 03 3500,decent a/c temps,a little uneven right to left but what concerns me is that I do not have much air coming from the vents and I hear a whole lot of air noise behind the dash.I am not afriad to tear it down and fix I just wanted to know if anybody has taken care of this themselves that can lend some advice other than taking it to the dealership.It has 140k miles on the odo so its way outta warranty.,I am my own wARRANTY CENTER....[duhhh]

It's probably either a blend door or recirculation door issue. Try a search on this forum, both have been heavily discussed.

Good luck

There is a step by step with pics on here on how to replace the recirc door box. Mine went out last month at 11K miles.

On the passenger side under the glove box remove the 3 screws on the fan assy and pull it down and out. look up the hole and see if your recirc or blend doors are laying over the fan hole or opening. This should lead you in the right direction.

thats what it was the door was laying over the fan,I pushed it up and screwed it to where it is always on recirc,for now