I don't know if this is a normal issue for 2006 g35 coupe, but when i step on the brake and move my transmission back to Reverse, i can 3 or 4 clicking noises in 1 second and some time happen when i put transmission on Drive too.. the noise came under the car

 

more than likely its your axle, take it to the dealer.

 

Search for "rear axle click" and you'll likely find the answer to your problem. The dealer should be able to fix the problem if your car is still under warranty. It is a very common issue plaguing the G35.

 

i though axle clicking when you drive..
I hear a click EVERY morning when I shift from P to R, then R to D. Is it covered under the drivetrain warranty?