I have an 06 350z. I had recently changed front control arms, inner and outer tie rods, coilovers because it was making a clunking sounds on the front left side. After replacing its still making that same sound. Any opinion what it coyld be?

 

Check the engine mount bolts on the bottom. I too changed a lot of parts and was just a loose bolt. One side was making the sound only. But bkth bolts where a bit loose.

 

Hopefully is a loose bolt.. I'll check on that.. Thanks..

 

This is usually the Compression Rod bushing. Most people replace them with Whiteline or SPL. It's a common front bushing to fail, especially on lowered Zs and Gs.
Here's a LINK to a how-to guide on this forum.
-Icer

 

I'm having the same issue right now as well. I too changed the upper control arms, inner and outer lower bushings, tie rod ends and still this god awful clunking noise when there is a weight shift usually when decellerating or making turns. hopefully i can piggy back off your post for the answer.

 

I had a clunking sound recently. I changed the front lower control arms which had bad bushings and I changed the compression arms even though they looked good. I also replaced my lower ball joints since both were bad.I still had a clunking sound although it was not as bad. My struts were replaced before this so I know those were good. One day I decided to replace my front and rear anti sway bar bushings with urethane bushings. When I removed the rear bushings I saw they were cracked and work. When I installed the new bushings, the clunking sound was gone. Check your anti sway bar bushings and possibly end links too.