Will a transmission from dodge ram 1500 5.9 L work in the same truck but 5.2L?

No, a transmission from a Dodge Ram 1500 5.9L (Magnum V8) will almost certainly not work in the same truck with a 5.2L (Magnum V8). While both are Magnum V8s, the 5.9L typically used a heavier-duty transmission than the 5.2L. Even if the bolt patterns matched (which is unlikely), the torque capacity of the 5.9L's transmission would likely be significantly higher than the 5.2L engine can produce, leading to potential issues. Further, the computer systems and associated wiring harnesses would be incompatible. You'd need a transmission specifically designed for the 5.2L engine.