2001 Crown Vic front end popping

I have a problem. My 01 crown vic has a popping noise in the front end whenever you push down on it. Changed ball joints, everything in the steering, nothing fixes it. Stabilizer bar had loose screws and threads were stripped. Replaced screws with bolts & nuts, and was fine. Started making popping again, bolts had come loose. Put on lock nuts and was fine. Popping starts again. Bolts still tight, and popping still there. Any one can help, or have had this problem before? It's driving me nuts. Thanks

Have you checked the body bushing bolts? We have had a few of those loose and cause a noise.

can i ask why you just never replaced stable lizer link's and bushings?