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Oil Leak on 2004 5.3 near/above starter

Mattt
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Mattt Enthusiast

Mattt

Posted
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Have this oil leak that recently started dripping with a vengeance.   This is on a high mileage 2004 5.3  in a Tahoe.  The engine will be coming out soon for a refresh or replacement, but this oil leak is making a big mess wherever I park, so I'd like to address it before it the garage floor stain is permanent.   With the engine running, I can see the drip come from above and somewhat to the rear of the starter, near the bell housing, but not quite on the bell housing.   It is coming from higher up in an area that I can't view.  

 

Want to take a stab at where this leak is originating from?  

Is that location for a leak a tell tale sign of one common leak that 5.3's suffer from?   I have attempted to look at the oil pressure sending unit, as I read they leak, but I can't get my eyes on it at the back of the intake manifold up against the firewall.   Is there a trick to getting eyes on that sending unit?

sefiroxx Enthusiast

sefiroxx

Posted
Posted

Snake camera

Leak is more likely a valve cover gasket. Leaks seeps down hill (towards firewall), down the engine head and block and then behind the starter.

  • Like 1
txab Senior Enthusiast

txab

Posted
Posted

Agreed. Look at cover gasket. Also there is a crankshaft sensor that is above/behind the starter that some leaks have been attributed to

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Black02Silverado Senior Enthusiast

Black02Silverado

Posted
Posted

Possibly the oil pressure sensor as well.  

 

In the mean time, go get a piece of scrap vinyl floor from a flooring store to put under the truck to keep the oil from getting on the cement floor. 

  • Like 1
Mattt Enthusiast

Mattt

Posted
  • Author
Posted

Thanks for the suggestions.   I will check those out.   Also, good idea on the vinyl flooring scrap to keep the garage clean.   

 

That oil pressure sensor is almost impossible to see back there.   Is the crankshaft sensor just as difficult to access in the truck?

Black02Silverado Senior Enthusiast

Black02Silverado

Posted
Posted
5 hours ago, Mattt said:

Thanks for the suggestions.   I will check those out.   Also, good idea on the vinyl flooring scrap to keep the garage clean.   

 

That oil pressure sensor is almost impossible to see back there.   Is the crankshaft sensor just as difficult to access in the truck?

The crankshaft sensor is above the starter here is a video showing it.  Youtube is your friend when it comes to fixing things.

 

  • Like 2
txab Senior Enthusiast

txab

Posted
Posted

You can get eyes on the OP sensor, it takes some work and plenty of light. Look for a few Ytube videos showing replacement.

 

Check cover gaskets

Oil Pressure sensor

Crank sensor

  • Like 1
  • 2 weeks later...
e_schott Enthusiast

e_schott

Posted
Posted

In my experience if it is leaking that bad its probably from the sending unit, but could be a valve cover gasket. While you can't really see the sending unit it is very easy to replace, no longer than a 10 minute job as long as you have a 3/8 universal joint and an extension to get back there and get it out. 

  • 1 month later...
Mattt Enthusiast

Mattt

Posted
  • Author
Posted

Sorry for not following up after the helpful replies.   I may try replacing the sending unit, but still can't get a solid line of sight on it.   I guess replacement is just done by feel since I know where it is located and the harness apparently clips on.   I will also have to take a look at the back of the valve cover gaskets as there is no obvious leak from the front, side or top of them.  Thanks again.

  • 3 years later...

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