2009 Chevrolet Epica knocking sound on suspension system

If the car was jacked up when the part was replaced, the suspension would have been hanging down. Any rubber bushings that were tightened in that position will be clamped in a permanent twist when the vehicle was set back down on the ground. In severe cases that will cause the bushing to tear apart.

If this noise just started after the part was replaced, look for shiny spots where paint has rubbed off to see if something is hitting. If nothing loose or hitting can be found, there is a tool called the "Chassis Ear" that might help. It's a set of six microphones, a switch box, and head phones. You clip the microphones to suspect points, then drive around while listening to the head phones.