[g-townmach]

Can anyone help me narrow down the Bosch part number for a rear (downstream) O2 sensor for my 04 Lightning.

I've searched online and have come up with 15644 but I think it might be for front (upstream) placement.

So is it 15717 or 15716... Those have come up in search also.

 

[ty.thompson1981]

15717. I just got mine in from rock auto. Cheapest I've found. $25 plus shipping. Works fine.