What are the current preferred brands for O2's these days? I have a couple of flakey ones (randomly occurring codes), that will need replacement this year.

 

Walker. Rockauto sells two models. I bought the more expensive, upstream part # 25024496, which to me were still cheap in terms of price. They work great.

 

Ditto on the Walker's from rockauto- I swapped out my front 2 and there have been no problems so far.

 

NTK. no issues 4k miles later. cleared my codes right up.

 

I just put in some Bosch ones but not enough miles/time to say if they're good in the long term.

 

Took advice from British mechanic, Due to issues had to replace 2 month old Walker sensors with NTK. No errors after 6 months.

 

I've thankfully not had to replace an O2 sensor since Walkers started being recommended here. (Knock on wood.) I can say that prior to that I had 2-3 Bosch O2 sensors be bad out of the box. If/when I need to replace one again I'll go with Walker.

 

I went with the Walkers (more expensive ones from Rockauto) on both Discos and haven't had any issues.

 

I tried Bosch, one bad out of the box. Replaced both with NGK, no problems and reading great since. Fingers crossed, lol.

 

NTK hands down. Tried both Walker and Bosch more than once. Both either threw codes right out of the box, or shortly after. The NTK aren't cheap, but on my finicky Rover, they solved my O2 issues.