Many owners of 2500 series Rams have experienced this phenomenon. It can range from just an annoying vibration in the front end to a downright dangerous situation where you cannot control the vehicle!

Dealers will replace tie rod ends, ball joint, steering stabilizers and track bars. They will also do alignments, recommend different tires and/or different wheels. Often none of these changes make a bit of difference and sometimes the problem goes away, only to return after a short time as one or more of the above described components begins to wear even slightly.
I've done a good bit of reasearch on this for a good friend with an '05 2500 CTD 4x4 we believe that with the help of a few online posts, have "cured" the problem. I believe that the "Death Wobble" is due to a fundamental design flaw in the suspension and steering of this truck.

We researched and found a 2500 owner who paid the dealership in excess of $1500 over a two month period to "fix" his very severe and dangerous Death Wobble issue with NO positive results. He then tried a component he purchased online for a little over $200 and after months of driving, the issue appears to be gone for good.

So we purchased and installed this on my buddies CTD last year and just like the guy we found online, the issue appears to be resolved in his CTD.

The item is a "Steering Box Stabilizer" and is available here:

http://www.genosgarage.com/products.asp?dept=142

Before purchasing, we also found a good write up on it on the "Diesel Power" website.

http://www.dieselpowermag.com/tech/d...zer/index.html

The original entry we found online gives a good explanation:

"The steering box stabilizer works because if you look at the frame rails you will see that the steering gear is located IN FRONT of the last cross-member. When anything under your front end suspension starts to wear out, a quick shock, like a bump at speed will cause enough force to cause the steering gear to flex which flexes the frame. Almost instantly, the frame flexes back, and through the suspension (a single wobble) forcing the other frame rail to absorb to energy and then back again. This resonant transfer of energy has nothing to dampen it (especially if you have extra hard shocks, the act more like stiff steel rods, not dissapating any energy) until you slow almost to a stop. More specifically, you panic, slow down, hope you don't lose control and cause an accident with someone running into you from behind, pullover, wait for your heart to slow down, then try driving again. The steering box stabilizer fixed the problem. It works because it boxes the frame in front of the steering gear and does not allow the frame rails in front of the last cross-member to act like a large tuning fork."

So, before spending a grand or more on trying to fix this issue at the dealership, I strongly recommend picking one of these up and giving it a try.