Coolant leak back of engine down oil pan, driver side

[InspectahDEck]

I've got *another* coolant leak pop up recently, this one coming from the back of the engine bay, down along the driver side of the oil pan. It's leaking pretty good, but I am not positive where it is coming from. I checked the back of the engine bay near the oil pressure sending unit and it does not look like the leak is originating in that area, as I have dye in the antifreeze and not seeing much there. A couple videos I recorded below, but help identifying the source of this would be appreciated

 

[Scottydoggs]

looks like its leaking from the head gasket. aka blown head gasket.

 

[InspectahDEck]

If coolant is leaking externally should I still expect to see some mixed with engine oil? I was going to change the oil this weekend anyhow...

 

[InspectahDEck]

I think you're right just started watching this video and it looks like the leak I have.

 

[Trey Hardy]

I've got *another* coolant leak pop up recently, this one coming from the back of the engine bay, down along the driver side of the oil pan. It's leaking pretty good, but I am not positive where it is coming from. I checked the back of the engine bay near the oil pressure sending unit and it does not look like the leak is originating in that area, as I have dye in the antifreeze and not seeing much there. A couple videos I recorded below, but help identifying the source of this would be appreciated

I’d lean towards a head gasket how many miles is on it? I’d opt for arp head bolts when you put it back together and make sure to get a quality mls ls9 style head gasket for replacement I think cosmetic is one of the better brands of gaskets

 

[InspectahDEck]

230k

 

[InspectahDEck]

05 yukon 6.0l

 

[strutaeng]

Wow. That's looks like a massive coolant leak there on the beginning of the first video.

Did the engine overheat at some point? Run dry or low on coolant? It's not common for these engines to blow head gaskets, unless they get overheated.

Edit: you sure it's not those little coolant plugs on the rear of the heads? Get an inspection mirror back there.

 

[InspectahDEck]

Certainly hasn't overheated. Yes it's leaking quite a bit, I have been driving it and no noticeable issues besides I have been topping off coolant regularly. Been a good two weeks this has been leaking, thought it was the heater tee which was leaking, after repairing that last night the leak continued today so I got under the rig to inspect...

 

[treehan77]

You check the connections to the heater cores etc, it’s in the firewall