* Front Frame Rails: The 4x4 frame will have heavier-gauge front frame rails to support the added weight and stress of the four-wheel-drive system.
* Crossmembers: The locations and design of crossmembers will be different to accommodate the drivetrain components.
* Mounting points: There will be additional mounting points for the front axle, transfer case, and related components on the 4x4 frame.
Therefore, you cannot directly swap them. Trying to do so would require extensive modifications and likely wouldn't be practical or safe.