Will a 6.1 liter hemi fit dodge 2006 ram 1500 4x4?
No, a 6.1L Hemi will not be a direct bolt-in replacement for a 2006 Dodge Ram 1500 4x4. While both are Hemi engines, the 6.1L was primarily used in heavier-duty Ram trucks (like the 2500/3500 series) and certain cars. The engine mounts, transmission compatibility, and various other components are different and require significant modifications, if it's even possible at all. It's a very complex and costly undertaking, far beyond a simple swap.