Jake 2015 GMC Yuk
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- Apr 26, 2024
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I have a 2015 Yukon with the 5.3 and 6L80 transmission and 150K miles. Oil is dripping from the starter as well as the other side where the bell housing meets the engine. The place where the oil cooler lines attached was dry and so was the fly wheel (looking through the access cover) so i don't think it is the rear main seal. I removed the upper oil pan (GM calls it the oil pan assembly) which involved removing the front differential and the electric power steering arm. I also removed the starter to see if there was oil coming from the sensor above the starter but that was clean. The upper oil pan does not use a gasket for 2015's although older models do. I paid a lot for dealer RTV and also bought the 3 black O-rings from the dealership - those go into the upper oil pan before you replace it. Oil was coming from all four corners of the bottom of the engine block. As long as i was under there, I replaced the oil cooler lines (took 1 week from GMPartsGiant $70 including shipping) and the transmission cooler lines (Napa $120), transmission filter and gasket. For what its worth, removing the transmission pan was much easier in my example and didn't require levering down the exhaust like you see in a lot of videos.
Bolted it back together and it still leaks, although it leaks a little less, still drips down both sides where the transmission meets the engine. I removed the intake manifold but it is very difficult to see if the oil is coming from the valley pan (at the back of the engine) or from the head gaskets. It seems more likely that the valley pan is the issue because if the head gaskets were bad, they would BOTH need to leak to explain why oil comes down both sides of the engine.
I've tried the die, mirrors, pictures, etc. I'm reluctant to do the valley pan without confirming first where the oil is coming from. Does anyone have any suggestions? Or experience replacing the valley pan gasket? Is a valley pan gasket a common issue in these models?
Thank you.
Update 5/6/2024
I am ordering the parts to do the Valley Pan. I know i'll need to remove the High-pressure fuel pump and those disposable fuel lines that sit under the air intake manifold. But do you need to take the fuel rails off to get the valley pan off? Also, if i DO take the fuel rails off, should i replace the injectors while i'm at it? Thanks for the answers so far!
Bolted it back together and it still leaks, although it leaks a little less, still drips down both sides where the transmission meets the engine. I removed the intake manifold but it is very difficult to see if the oil is coming from the valley pan (at the back of the engine) or from the head gaskets. It seems more likely that the valley pan is the issue because if the head gaskets were bad, they would BOTH need to leak to explain why oil comes down both sides of the engine.
I've tried the die, mirrors, pictures, etc. I'm reluctant to do the valley pan without confirming first where the oil is coming from. Does anyone have any suggestions? Or experience replacing the valley pan gasket? Is a valley pan gasket a common issue in these models?
Thank you.
Update 5/6/2024
I am ordering the parts to do the Valley Pan. I know i'll need to remove the High-pressure fuel pump and those disposable fuel lines that sit under the air intake manifold. But do you need to take the fuel rails off to get the valley pan off? Also, if i DO take the fuel rails off, should i replace the injectors while i'm at it? Thanks for the answers so far!
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