I am needing to replace the oxygen sensors in my 2000 Ranger. I think I heard somewhere that you should not use the Bosch brand to replace. Does anyone have any experience with the Bosch oxygen sensors or if there is a better after market brand?

Thanks

 

Bosch or Denso are fine to use as replacement of OEM O2 sensors

Have used both without issue over the years.

Upstream O2 sensors(close to engine) are used by computer to determine if air/fuel mix is too lean or too rich
Downstream O2 sensor(s) are used to test if Cat converter is working, they don't effect performance

You only need to replace upstream sensors unless you have a specific DTC code(check engine light on) regarding downstream sensor, downstream sensor(s) last twice as long since they only see "cleaned" exhaust after the Cat

 

Reviving an old thread as I had "as Ron D said" to replace my downstream sensor (the one after the catalytic converter) because I had a DTC code for it. I used a Bosch Exact Fit (per the Bosch website) for my 2003 Ranger 3.0 Automatic for the one after the CAT (Downstream). While I had the inner fender wells out I realized I can access the sensors very easily and after 244K miles on the original ones I decided to change those also. These are the 2 before the CAT (Upstream).

Here are the part numbers:
O2 Sensor Downstream - Bosch part number 15716, you only need one.
O2 Sensors Upstream - Bosch part number 15664, you will need 2.
One for each side of the engine, they are located right after the exhaust manifold (there is one on the driver's side and one on the passenger side (bank 1 and bank 2).
I hope this helps.