I have a 2005 s type with std suspension. I have replaced the rear lower and upper control arms and am still getting noise (groaning sound from rt rear of car. I took to dealer. They said the rear struts need replaced, I will go for that 75,000 miles. But also claim the rear springs have worn and need replaced. I have had 2 of these cars and have never heard of rear springs needing replaced. any feedback would be appreciated

 

Ask them for the ride height specifications and measure your current ride height. If its riding low, that's the only possible reason I can think of that they might recommend replacing the springs.

 

More likely to have broken springs TBH. The ends usually snap off them. My old Mondeo front springs where in a right state. One snapped on me as I pulled out the drive and when I managed to pry the front ones off the car I found all the ends snapped off.

 

The Vehicle Specifications Booklet (VSB_07_2004.pdf) has all the info your need.

 

It is just a shot in the dark but my guess would be it is the top mount (XR856159 I think?) or the anti role bar drop link. (C2D49528 I think?)
Both are known to make noise.
But without investigation it is imposiable to know.

Mellow