Question on steering rack noise
 

When I lied under the car looking up while someone turn the wheel to both side. When the wheel turn MAX to either side, I hear a sound of metal hitting feel like it comming from the inside the boot. So I guess I will take off the boot to see that is wrong in there.
But today, I found a picture of the steering rack on Ebay. Now I can see the part inside there. It doesn't look like it has any moving part or join that make the noise. So maybe that noise is normal?

This is the pic here.
http://i18.ebayimg.com/02/i/05/7d/f0/8f_12_s.JPG
The sound I feel like it commingg from is on the left end (black).
Any thought?
Thanks.