I was hearing some knocking sounds whenever I hit a bump so I took my car to the dealer and they said its nothin wrong with my car I have lowering spring, sway bar can anyone help me figure out where the noises coming from

 

probably your sway bar end links

 

If I understand correctly & you changed the sway bars, it sounds like you don't have enough grease in the bushing that holds the sway bar. Also, most likely they're also not torqued down enough

 

Remove the sway and endlinks then try to replicate the sound
If no sound, you narrowed down the problem...if you still hear it, you narrowed down the problem

 

It been on the car just started hearing the sound not to long ago

 

You don't have to remove the sway bar(s), just unbolt the endlinks and tie them to the sway bar so they don't rattle. If the noise goes away, you know where the problem lies. Removing the bars is an unnecessary hassle.

 

I agree, no need to remove the bar and go through that hassle...I have the 13 g37x myself. I had a similar noise because when I swapped my stock for hotchkis set, I didn't put enough grease. Not to call out the obvious but you took out the bodies from the trunk too right?
Um the only other thing I can think of is not torquing the shock absorbers nuts ?