ya I had the problem and took it in and got a new seat and then I got it back and it still squeekd so good luck...

 

I have a 2004 G35 Sedan Sort package with the same problem. The car has 11,500 miles on it and has been to the dealer 5 times. They even had the DTS come out, he found a stripped anchor bolt, hello there are torque specs. In the process they put deep scratches on the door sill. I wrote to the owner of the dealership and Infiniti Consumer Affairs. The noise came back eventually. Items done to the car (1) replaced lift link (2) replaced seat (3) peened the metal down (4) welded anchor nut (5) replaced stripped bolt. Bradshaw Infiniti Greenville SC. Please let me know what dealerships you are going back to. Thanx