2005 INFINITI FX35 User Comment / Complaint

I purchase a 2005 infiniti fx 35 in november 2005. after 1000 mile the brakes started squeaking when backing up (whether cold or hot). at approximately 5000 miles riverside infiniti (purchase vehicle from) installed tsb upgraded brakes. the squeaking went away for about 1000 miles and it came back with a vengeance. the dealer did not and currently does not have an answer. i currently have 15k miles on the car and now i am receiving a groaning metal to metal sound when i apply brakes at very low speeds. i took the car infiniti of escondido and they stated my tires are "cupping" and i did not have my wheels balanced during my last rotation and that is the reason why i am having metal to metal noise? please help in resolving this issue.