We had a Acura TL in to check out for a subframe needing to be welded. What we found was the left front lower control arm forward bushing had separated from the rubber allowing the control arm to rub against the subframe. Unfortunately the metal to metal contact has occured for so long the subframe area is now paper thin. The damage has been done, the subframe now requires replacement. If the bushing separation had been spotted years ago the costs would have been minimal but now it will take one or two thousand dollars to repair. Having your vehicle serviced by a certified technician may cost a little more in the short run but could save you a lot in the long run.