Here's why:
* Different Engine Mounts: The engine blocks and associated mounting points are different between the 5.2L and 4.7L. You'll need custom engine mounts, which will require fabrication or finding aftermarket solutions (unlikely to exist readily).
* Wiring Harness and Computer: The 5.2L and 4.7L use different engine control modules (ECMs) and wiring harnesses. You'd likely need extensive rewiring, potentially requiring a custom harness, or attempting to adapt the existing harness – a very challenging task.
* Transmission Compatibility: While both might use similar transmissions, the exact compatibility would need careful investigation. The bellhousing pattern might be different, requiring an adapter or a transmission swap.
* Exhaust System: The exhaust manifolds and system will be different and require modification or replacement.
* Other Components: Other components like the alternator, power steering pump, and accessory brackets might have different placements and require adaptation.
In short, the project would involve significant mechanical expertise, custom fabrication, and potentially substantial cost. It's far more complex than a simple engine swap. Swapping a 4.7L into a 4.7L or a 5.2L into a 5.2L is much easier. The effort involved would likely make it impractical and cost-prohibitive compared to finding a used 4.7L engine for replacement or repair.
