Is it Oxygen Sensor time?

Just about to turn over 100K mile marker.
Would like to change out upstream Oxygen sensors.
No dash lights, just preventative maintenance.
Also, should I go with Denso? got a part number?

thanks guys.

 

Wait for one to fail. Replace all four at same time. Don't bother replacing preventatively, IMO.

Yes, buy Denso. No, don't buy from fleaBay, scAmazon, or WallyMart, you most likely will get counterfeits.

 

I didn't replace mine until 177k miles when one threw a code. I would wait. One of our former members claimed his truck had more torque afterwards but no one else has reported that. My truck drives the exact same.

 

No difference in performance after changing my O2s and clearing a 200-mile driven P0031 code.

Here are all 4 Densos. The 169s are the upstream 2. 161 is downstream driver side, 162 is downstream pass side.

 

That’s strange you have two part numbers for the rears, they should be the same

 

Speaking of an 04 DC only, the rears are different. The harness for driver side is approx 6" longer. Which means it's difficult if not impossible to swap sides for troubleshooting to see if code follows.

These are OEM from Cool Springs dealer @Roman on an 04 DC....

Rear Oxygen Sensor, Left 89465-09320
Rear Oxygen Sensor, Right 89465-09380
Ft Oxygen Sensor, Left 89465-0C150
Ft Oxygen Sensor, Right 89465-0C140

 

Red headed step truck!

 

I have a 2006 4.7 and changed the originals at 290k. The truck ran smoother and upped the MPG slightly.

 

Absolutely. Just plotting a voltage over time plot shows degradation of the sensors without necessarily failing.

 

Only for the hell of mentioning it, I can't remember which it was, but one of my 02 went out at around 69k miles. No joke. I didn't take my own advice and replace all 4. It's been at least 18-24 months and a few thou miles and no other issues.

Point being, these can fail early. They typically don't.