Cna you describe exactly what you mean by "burned out"? Is it physically melting?
Well, there is nothing in the truck that can electrically damage the crank position sensor; it receives power on teh same 5 volt computer circuit that powers up the other sensors (TPS, MAP, etc...). If it was high voltage in the electrical circuit then you would be experiencing failures of other sensors as well.
I am going to go out on a limb here and guess that you are installing sensors from a discount parts store like Autozone, Advance, or pep Boys. These types of stores buy their parts from the absolute cheapest overseas suppliers they can find; usually they are of pretty poor quality and fail easily. I would suggest that you might want to buy a sensor from your local Dodge dealer parts department; I have never had a genuine Mopar crank sensor fail after it was replaced, and in our shop we have installed many crank position sensors.