Any point in changing the rear 02 sensors?

[02Lightning]

I just replaced the two fronts with NTK at 135000, just wondering if I should replace the rears, or just wait till they fail. As far as I know they just tell you if your cats are doing their job.

 

[Foggy]

Wait til you have an issue on the rear.. they are just tattle tale sensors
It's the fronts that actually affect the engine

 

[wsteele]

I just replaced all four, at a similar mileage. I figured for the extra $100, choosing when I did it, versus scrambling around with the emission test notice in my hand was worth it.

 

[Foggy]

I can see doing it in the areas that have the mandatory emissions testing...
Thank Goodness we don't here in KS