I just replaced all the struts on my 99 lesabre,and now when I go over bumps i get a clunking noise in the front end.It didn't do it with the old worn out struts ,163k on car.

Check the spring retaining nut, sometimes you can get a bit more tightening up on it once the weight of the car is on the spring.

How did the upper strut mount/bearing units look? Did you install the spacers on the strut rods in the same positions? Were the compression dampers in good condition?

As wright indicated, you may need to fully tighten the upper strut nuts, too. If you open the hood, remove the upper strut covers, and slightly jounce the front end, can you observe any relative movement between the strut rods and mounts?

Yup thats what it was i put the impact wrench on them and the passenger side was loose.Rides great now
thanks