I need to replace the O2 sensor on my brothers expedition. He said he would spray penetrating oil on it a couple days before I get there. Do I need to make sure the penetrating oil is O2 sensor safe? I have Deep Creep and Liquid Wrench in my garage and neither says anything about being O2 sensor safe.

What do you think?

 

If you are spraying it on the sensors that you are taking out, it's doesn't really matter. clean up any residue with brake cleaner before installing the new sensors. the replacement sensor should come with nickel anti-seize on the threads, if it doesn't, put some on. You should use only Bosch O2's for replacement.

 

Thanks for the response. After the o2 sensor is out, we will spray the crap out of the arae of the o2 sensor with brake cleaner. I just didn't want to hose up the new sensor.

Lets just hope the plug and sensor comes our of this truck with 160k miles on it!

Thanks guys. This site is a world of help!

 

Make sure you have the correct wrench. You may not be able to get a socket in there, in that case there's a crowfoot for it.

 

It's the drivers side front o2 sensor. Once I get it unplugged, I think I can get a box end wrench over the wires and in place. I'll bring my o2 socket, swivel, and I have those plumbers wrenches that are like a box end with only 5 of the 6 sides.

 

I just changed one on my Mom's Jeep.
I use PB Blaster only. It really gets in there.
What I do, when I get ready to change an O2 is.....
(1) With exhaust hot, PB Blast the bung area where the O2 threads in, making sure you blast the threaded area really well.
(2) Wait a couple of hours, after the exhaust has completely cooled down and then PB Blast the area again. Don't be shy with the Blaster.
(3) I let it sit over night and then the next morning I give it a quick shot of blaster in the threaded area.
(4) O2 should come right out for you. I have never (knock on wood) had a problem removing an O2 using this proceedure.

The reason I spray it when it is hot then cold. Is the threaded bung and the
O2 threads expand and contract with the heat and cool down. Actually, most metals will do this.

When I did my Mom's jeep, I literally was able to give it a little tug on the nutted area of the O2 with an open end wrench (10 point), and it broke free very easy.
I unthreaded the O2 by hand, no joke. Her Jeep Cherokee had 152 k on it when I changed the O2.

Good Luck,
TJKinCNY