So I'm at 103k miles, nearing 104k and wondered about the O2 sensors. AFAIK they are original to the X5.

Is this something I should change proactively or just wait for a check engine light? I imagine I'll improve my gas mileage a slight amount but it'll take a lot of miles at that slightly better gas mileage to pay for four O2 sensors!

FWIW, I'll DIY it so I'm looking at my time (worthless apparently) plus just shy of $500 for the sensors.

What's the collective wisdom out there?

__________________
Kirk
Las Vegas
2016 X5 40e Mineral White/Black Dakota Leather, ZLL, ZCW, ZDA, ZDB, ZPP, multi contour seats, rear side window shades, HK stereo
2011 E90M3, 6-speed manual