Can a 2005 Chevy Malibu 6-cylinder. engine subframe fit in 4-cylinder . engine?

No, a 2005 Chevy Malibu subframe from a 6-cylinder engine will *not* fit a 4-cylinder engine. While some parts might appear similar, the mounting points for the engine, transmission, and other components will be different. The 6-cylinder engine is significantly larger and heavier, requiring a reinforced subframe. Trying to force a 6-cylinder subframe onto a 4-cylinder car will result in incompatibility issues.