Anyone know what this is?

[adic27]

I cleaned it by using super clean. Hope that'll be alright. Don't know if it'll make a difference

 

[sportyrick]

brake valve, don't all those hoses go to brake chambers?

 

[flattracker]

looks like an encrusted air dryer. to get that way it probably has been dripping oil through the relief valve. that's the part not encrusted. I would be concerned about your compressor needing a rebuild, since that is the likely source of the oil. Keep in mind that is engine oil coming out. Post a picture post cleaning.

 

[adic27]

looks like an encrusted air dryer. to get that way it probably has been dripping oil through the relief valve. that's the part not encrusted. I would be concerned about your compressor needing a rebuild, since that is the likely source of the oil. Keep in mind that is engine oil coming out. Post a picture post cleaning.

It's in the back right above where the last driveshaft connects to the pumpkin yoke. The air dryer is way towards the front near the compressor or inside it or insidesomething, right? I might be rong. Here's a pic of it after cleaning.

EDIT: It's pretty small, BTW

 

[PhilipE-SKO]

Air brake quick release valve.

As much crud as you removed. The air compressor is passing oil. If you don't have a air dryer. I would install one.

 

[DoubleO7]

Air brake quick release valve.

As much crud as you removed. The air compressor is passing oil. If you don't have a air dryer. I would install one.

Why install an air dryer to fix a worn out air compressor passing oil?

He posted it is directly above the rear axle u joint that was also covered with oil and dirt.
But I would agree as the background would also be covered the same if the pinion seal was slinging oil.
That valve is probably how and why the front of the pumpkin was encrusted.

To the O.P.
Go look at the same dump valve for the front brakes Look up behind the front bumper at the bottom of first cross member of the frame.
If that one is encrusted like the other, your compressor is doing what Phillip says above

 

[PhilipE-SKO]

Why install an air dryer to fix a worn out air compressor passing oil?

If you look at his location. He is in TX. That means high temps and high humidity for a large part of the year. High humidity means water in the air system. Water causes more problems in a air system than engine oil from a bad compressor. But yes you are right the compressor does need changed out. The addition of a air dryer will stop oil and water problems.

You mentioned a seal needing replaced. A seal leaves a splatter pattern. The splatter pattern is narrow and in a straight line. That pic does not show a splatter pattern that a bad seal would produce. All the built up oil is on one valve. Nothing on the metal its mounted to. That release valve vents down towards the camera.

The front valve might not show the same oil build up. Oil is like water it takes the least path of resistence. If its easyer to get to the rear valve. It goes there.