The least expensive way to go, would be another 6.4, just saying.

 

that is true but not exactly what he was asking, i would use the 06 cummins so you could use efi live on it later down the road if you wanted to

 

The 6.4 has dual turbo, & Spartan tuner will give you 315 HP

 

I think he may be a she

 

I was thinkin the same thing

To the original poster, it really depends on what you want and how much you want to spend. A 5.9 Cummins would be the most common swap, and therefore easier and most likely least expensive. Now on that topic, if you go with an older 12 valve Cummins, it will be much less trouble to swap in as it has no electronics. You could go with a newer commonrail Cummins, but the engine will cost more, the parts for it should cost more, and overall the swap will cost more.

 

oops!!! sorry