Check if axle center nut is tight. wheel would wobble too if it got loose.
Rotate axle by hand and feel where the most feedback from clunk is coming from.
With 37k even very hard miles its too early for issues@rear end. My G has 225k km with lots of track and autox time-still on stock axles.If you know anybody close to you with Z ask them to test their car.
Z has drivetrain " lash", it might even be normal. Mine clunked since new if I was bit clumsy with clutch at very low speeds- like parking.
__________________
2016 370Z Base/Setrab/AEM/Uprev/M7 Japan/Magnaflow/Quaife/Wilwood/300 whp
2003 G35 sedan 6MT(good bye-after 15 years together )
|