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Possible Crankshaft Position Sensor Leak

nGAbear

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nGAbear Enthusiast

nGAbear

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My Suburban began leaking oil pretty significantly recently and I crawled underneath to check the rear main, luckily that area is dry.

 

Next I began removing the starter so I could check to see if the crankshaft position sensor was the culprit. I was having a bear of a time actually removing the starter so I didn't take it completely out. When I removed the bolt that was nearest the engine, there was a lot of oil. So here's the question, is there anything other than the crankshaft position sensor that could be leaking just above the starter? Where would the dipstick tube/housing leak if it leaked?

nGAbear Enthusiast

nGAbear

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Well, I finally swapped out the sensor and changed the oil/filter. The truck is running great!

 

After reading about the importance of that sensor it doesn't surprise me that the truck is purring as well as it is. The bummer is that the engine is still leaking oil.

 

After cleaning up the underside it appears that the pan gasket and maybe the rear main is in fact leaking.

 

I've looked through this forum about replacing the rear main and haven't been able to find a lot about the process. Is this tough to do? Is Rear Main the actual term/part? I'm looking through my Haynes manual and on AllData.

nGAbear Enthusiast

nGAbear

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I've got a new RMS, pan gasket, and J 41479 Crankshaft Rear Oil Seal Installer on order. I'm looking to take care of this project over the weekend.

 

How difficult is it to get the flywheel off? Any suggestions or words of wisdom for me from those of you who have done this before?

Gurrzt Enthusiast

Gurrzt

Posted
Posted

There MIGHT be an oil sensor in back of the intake that is leaking, on my 2001 Z28 (Sara) that was the culprit.

 

The oil was running down the rear of the engine, and made it appear to be a rear main seal sepage.

txab Senior Enthusiast

txab

Posted
Posted

There MIGHT be an oil sensor in back of the intake that is leaking, on my 2001 Z28 (Sara) that was the culprit.

 

The oil was running down the rear of the engine, and made it appear to be a rear main seal sepage.

 

 

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