Will a 2005 Dodge Ram 1500 5.7 engine fit in 2003 5.9?
No, a 2005 Dodge Ram 1500 5.7L Hemi will not be a direct bolt-in replacement for a 2003 Dodge Ram 1500 5.9L Magnum. While both are V8s, they have significant differences in engine mounts, accessory placement, wiring harnesses, and computer systems. The engine block itself is also different. It would require extensive modifications, likely beyond the scope of a typical DIY mechanic.