Hi. 2007 FJ 4WD w 160k miles error codes P0420 passenger side and P0430 driver side codes came up. Catalyst inefficiency meaning the catalytic converters were no good. Ran cat cleaner through the gas tank and no change. Dealer wanted 4g for new cats including install. I paid $750 total. 2 Eastern Catalytic cats from RockAuto at $250 a piece and 2 Denso air/fuel sensors at $125 a piece. I tried the cheaper UltraPower sensors but their clip didn't fit into the FJ's sensor clip. The job is easy and I will outline it here. Basically it includes taking 6 nuts off the exhaust manifold as it attaches to the engine and two nuts where the exhaust connects to the next rearward exhaust pipe.