On our G35's the hood hinges tend to seize. Mine was so bad the hood was very hard to open and close and it gouged away the paint on the fender. So I sprayed WD-40 on the hinges while working the hood up and down and the problem went away. Any time I notice any resistance in the hinge (popping/clicking sound) or every few oil change I will spray it again, works just like brand new second hand.