I think you're right 54, and I think that is not the leaky part.
If you look at the spray pattern, it looks like a high velocity spray from someplace below that because the film is missing directly above the tubing. I think that looks like an axle seal (or main shaft) gone bad, and it is getting thrown up on the frame.
But hard to tell without knowing where we are on the truck.
Here's what I found. It most definitely is the parking brake cable, which obviously can't be leaking. I found on my truck that some grease from the front U-Joint on the driveshaft had flung some grease out onto this area, but nothing for me to be concerned about. My situation looks entirely different, i.e. blobs of grease vs. a thinner 'wet' type of substance on src4usarmy's truck.
Could it be the seal on the back of the transfer case that's leaking? Or if he's 2wd, the tailshaft seal on the transmission.
When you wipe some of it off with a white rag, does it smudge red, or black?
That U joint looks suspicious, as it is also coated with the 'stuff'. So it could either be leaking from that seal (red tran fluid) or just some oil/grease coming out of the u joint (black stain).
It could also be that when filling some other fluid, it was spilled on the shaft and then got flung all over.
I guess I would clean up the area, check your trans fluid level, and then look for it again in a week. :smoke:
Bringin up an ole thread here, but mine looked just like this! Believe it was the them little bolts on the back of the trans-case...Had one that was pretty loose I seen several people on here having issues with that problem...