Stuck on changing starter 2007, 3.7L Liberty 4x4

[idiotTryingToChangeStarte]

I am trying to replace my starter.

I am stuck at removing the last bolt from starter (Red Circle)
This spark plug looking thing is in the way(blue circle), Can I simply unscrew it, then screw it back in, and what is it?

I guessed O2 sensor, although I know zero about cars.

Also, what is this oily substance in the drive shaft, gear oil correct?(removed the drive shaft to get to the starter), do I need to do anything specific when reinstalling the driveshaft?

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[tommudd]

I am trying to replace my starter.

I am stuck at removing the last bolt from starter (Red Circle)
This spark plug looking thing is in the way(blue circle), Can I simply unscrew it, then screw it back in, and what is it?

I guessed O2 sensor, although I know zero about cars.

Also, what is this oily substance in the drive shaft, gear oil correct?(removed the drive shaft to get to the starter), do I need to do anything specific when reinstalling the driveshaft?

You must be registered for see images attach

Yes 02 sensor
unplug and unscrew
Front drive shaft just reinstall, while off check the rear cv and see if boot is deteriorated

 

[idiotTryingToChangeStarte]

Yes 02 sensor
unplug and unscrew
Front drive shaft just reinstall, while off check the rear cv and see if boot is deteriorated

I need to unplug, then unscrew? Do I just pull ******* it from the base?
Thanks Tommudd for stopping in to help this idiot

 

[kejobe]

The part you circled in blue is the O2 sensor. That will unscrew from the exhaust. Follow the wires up from the sensor and you will come to the harness for it. Unplug the harness BEFORE you unscrew the sensor or you risk damaging the wires.

 

[ltd02]

Follow the wires up to the connector and unplug. There should be a tab you press and then pull sensor end out. You don't want to twist the wires up trying to unscrew it with the plug connected. The oily substance in the ends of the front driveshaft is CV grease. There are CVs on both ends with boots to protect them and contain grease. Make sure they are both good while you are in there. The CV boot nearest to the transfer case is recessed and tough to see. If you see grease/oil right near the front differential beyond the end of the shaft then you may have a pinion seal leak too. The transfer case has ATF+4 in it if it's oily on the very end at the tcase.

 

[JasonJ]

I need to unplug, then unscrew? Do I just pull ******* it from the base?
Thanks Tommudd for stopping in to help this idiot

Just pulling ******* it will destroy it.. and make your life a little more miserable. You see how it has a hexagonal shaped nut-looking thing at the base, where it meets the exhaust pipe? That's where you can put an open end wrench of the correct size...

Spray it liberally with penetrating oil first, to help loosen any corrosion that will make it difficult to get out. It looks in good shape, so it should come loose pretty easily- but like others said, unplug it first so as to not twist the wires.

Also, when putting it back, be careful not to cross-thread it when screwing it back in, the threads on the sensor can be easily damaged, since the exhaust pipe threads are generally much harder.

 

[HoosierJeeper]

Get an O2 sensor socket (any auto parts store will loan you one) and put it on a breaker bar. And do it with the exhaust hot. I had one of them out in literally one push on the breaker bar.