Rear o2 Sensors

[Blue_Oval_Ford]

Ok, I did a search and could not find any information on how to remove those pesky rear o2 sensors. I tried spraying some wd40 on them but they will not budge. Also you can't get a wrench or socket back there because of the tight space (4x4). Anyone ever replace these?

 

[Eneurb]

Heat up the bung on the pipe to free up the sensor. There are special tools available to make oxygen sensor access a bit easier.

 

[Billy177]

belive or not i just used an adjustable wrench and moved my arm in ways that it is not supposed to move but i got them out

 

[Blue_Oval_Ford]

Thanks for your help guys,

Well, I got the rear most o2 sensor off but thats it. I have both the o2 sensor removal tools and there is no way to get a wrench in there, not even a 3/8 breaker bar. I even warmed up the truck by taking it for a long drive this morning. This is really starting to pi$$ me off.

 

[Eneurb]

Sometimes exhaust heat just isn't enough. Be careful of taking the threads out with the sensor if it is too siezed. My normal procedure for a siezed O2 sensor is to heat it red hot and they usually come out with out too much of a fight, but at times the threads need to be chased.

 

[RickOTR]

The easiest way to do it is to disconnect the o2 sensors then remove the exhaust system. It's not as difficult as it looks, just time consuming. If you had a 2wd it would be a snap, but that 4wd sucks due to the transfer case, and also it being a short wheelbase. Our you can remove the transfer case... once again not that difficult.

 

[Eneurb]

I think I'd stick with the heat.

 

[Lloyd10977]

Thanks for your help guys,

Well, I got the rear most o2 sensor off but thats it. I have both the o2 sensor removal tools and there is no way to get a wrench in there, not even a 3/8 breaker bar. I even warmed up the truck by taking it for a long drive this morning. This is really starting to pi$$ me off.

This might be a silly question but have you tried a crowsfoot wrench? It needs no clearance at the top just like an open end wrench and because it fits around 5 of the six sides of the hex it will allow you to apply almost as much torque as a six sided socket or box end wrench. And because you can even use an extension from either side of the crowsfoot, you have some flexibility in positioning your ratchet.

 

[Blue_Oval_Ford]

I have the crowsfoot wrench and there is not enough room for a ratchet or breaker bar to move in either direction. The o2 sensor was not on that tight so heat is was not the problem. However, I did get all of the sensors changed by disconnecting the exhaust from the manifolds back to the muffler then slidding it back enough to reach the sensors. It was a lot of work, but worth it.