FYI: yes, any rear-end swap will require that the rear-end ratio be updated (with a tuner or similar device) in the car's computer (on the older LXs). However, that is something the service department at any Dodge dealership can easily do if a tuner is not available or within the budget. The dealership option makes the most sense IMHO when the rear-end gear update is the only reason for purchasing a tuner. Save that money and go to the local dealership instead.

Now, I would be remiss if I didn't at least mention the possibility that some dealerships may want to charge much more money to do this tune update than others. So anyone considering this option would do well to call around and get some quotes or unofficial estimates before going to any one in particular. Or even go in person and say you're there for a recall check, and while they're looking at it, mention you'll be swapping out the rear-end soon and ask what it might cost to bring to them for the TCM update.

Hell, he might tell you to come by on a dead afternoon and they'll do it gratis...who knows. But you can bet your bottom dollar that there are some out there that would try to squeeze every last penny out of you for such a non-std. service, and those are the ones you'd obviously want to avoid, if at all possible.