I just got a used F Sport performance axle back. I also currently have the 3rd gen f sport intake with the sound generator tube. Once I change the axle back, should I get an ECU tune? I heard it being suggested. I'm assuming it needs to be some sort of a custom tune?

 

A tune is not necessary unless you modify the intake beyond OEM. You can port the intake manifolds and they work without a tune, but you cannot upgrade to the Tundra's bigger throttle body without a tune, as the ECU will not understand where it has access to so much more air. A tune