I’ve been chasing this issue for a while now. My rear right passenger side coilover keeps clunking and rattling. It sounds like the top hat is hitting against the body or spring, but all the bolts are tight. I’m always experiencing that side being soft, bouncy, and being unstable.

I’ve already replaced the strut with a new ones from BC, also changed the top hat, adjustable camber arms, and sway bar links but the noise is still there. Almost brought it to multiple shops and preload is set and spring along with everything is tight and secure. Does anyone have any suggestions on what else I should check or any suggestions?

 

Hey, that clunk on the rear passenger side of your BC Racing "divorced" coilovers (separate strut + spring) is a very common complaint on G37s. Even after swapping the strut, top hat, camber arms, and end links, the noise often comes from a worn or faulty shock cartridge inside the strut itself. Many owners fixed the exact bouncy/clunking issue by contacting BC Racing for a replacement cartridge (usually ~$100 and easy to swap). Double-check the center nut on the top mount (the big one holding the assembly together) is torqued properly too, as it can loosen and cause rattling. If you haven't already, try that first before sending the strut back.