1999 Chrysler Concorde thumpping sounds

"i have replace the whole front end of the car"

Did you really replace the bumper cover, radiator, headlights, and hood? Please be specific as to which parts were replaced and why you thought they needed to be.

Struts won't cause a thumping sound. Is the sound occurring at regular intervals and do you feel it in the steering wheel? Suspect a broken belt in a tire or a warped brake rotor. Does it occur on bumpy roads? Suspect loose brake caliper mounting bolts. If you hear a light rattling while driving through the parking lot, see if it goes away when you have the steering wheel just slightly turned either left or right. This will put pressure on the anti-sway bar links and make them stop rattling if that's the cause.

Caradiodoc