I am fairly confident that I fixed the axle clicking issue without the need for a new aftermarket nut or washer. I did the following on my older G35 when I replaced the wheel bearings (because there was a TSB to put moly grease on the axle flange) and never had one axle click with the car. As soon as I got my G37 I noticed the clicking daily.
So today I decided to take the axles out...cleaned up the splines and faces, grease up the axle, hub, and splines. When I put everything back on, I tightened the oem axle nut very tight. I used a steel pipe and breaker bar to really get on the nut. I don't have a ftlbs bar that goes over 75 but I can tell it is way over the FSM setting of like 80lbs, probably somewhere over 120 (did it while the car was on the ground with the wheel center cap off). The axle nuts came off too easy when I took them off the first time.
I took the whip for a quick drive and I didn't hear one click. It was just clicking constantly yesterday so I feel something I did worked !!
I realize most of you guys have newer Zs/Gs and can't touch the car while its under warranty...but maybe you can give it a try?
Here are the pictures: you can get this permatex anti seize at autozone and many other stores. I use it on pretty much ever bolt on my car too
Also the pictures don't show the inner side of the wheel hub, I lathered that up with anti seize too, making sure I got the face of it where the axle rests. And the inside hub splines too.
