My Chevy cobalt has a clunk/ bang going over certain patches of rough road. I have replaced everything in the front end. Struts, stab links. Sway bar bushings. Lower control arms. Ball joints. What’s left?
Get a noise finder like Scotty has and hook it up to various parts of the suspension.
Also check your motor and transmission mounts. Put a block of wood between the oil pan and a floor jack, and try to lift the engine. The car should move with the engine, right away. If it doesn't, there's a broken motor mount.
I have found the clunk issue. I replaced all the motor mounts. The main mount is oil filled…that was torn and all the oil gone. The other 3 mounts all torn rubber. No more clunk. The engine was sitting 4”;low and slightly crooked due to torn mounts. GM used very poor quality on all these parts.
Thanks for posting back with the fix. Well done!