Pontiac G6 knocking noise issue after flywheel replacement on Pontiac G6

Some Pontiac G6 owners report experiencing knocking noises after a flywheel replacement, which may be attributed to several potential issues. Rod knock is a common concern, characterized by a distinct noise that correlates with engine RPM, indicating possible problems with the engine rods. Additionally, damaged or worn main bearings can produce loud knocking sounds during engine operation, especially under heavy load. If the noise varies with vehicle speed, it may suggest suspension issues, such as a bad axle shaft, leading to pronounced metal-on-metal sounds over bumps. Problems with steering components, including the rack or gear box, can also result in knocking noises in the front end. Furthermore, some G6 models have reported cracked strut towers, which pose safety risks and should be addressed immediately. Lastly, worn lower bushings may create noise when contacting the frame. To accurately diagnose and resolve the knocking issue, a thorough inspection by a qualified mechanic is highly recommended.