Where is this fluid coming from?

2002 Ram 2500 CTD, automatic transmission with AC, with not quite 67,000 miles in western Pennsylvania. In the last 4 weeks, we have put around 300 miles on this truck after a period of relative inactivity. This afternoon I noticed fluid drips on the front stabilizer bar towards the right front, with more fluid on the right frame rail. The fluid is not coolant, engine oil, power steering fluid, gear oil, or automatic transmission fluid. The fluid is rusty looking, and has no inherent odor, it reminds me of silicone, rather viscous. Looking at it from above, it appears as though it is coming from the top housing of the belt tensioner. Is the tensioner fluid damped? The serpentine belt needs replaced anyway, and I was going to replace the tensioner along with it. Is this where the fluid is coming from? By the way, there is no evidence of a radial spray, like from a failing fan clutch. No noises either.

Thanks for the help!

Closer examination after removing the belt and belt tensioner revealed that the AC compressor has blown out it's oil.

Time for a new compressor. I couldn't really tell where it was coming from before.

does the ac work? maybe you just need to change the seal on the line rather then the whole compressor?

The compressor was leaking at the shaft seal, not at the manifold connection and again, not knowing how long it had been, I elected to replace the compressor. There was still a little charge left in it when I replaced it. It's getting evacuated and charged with refrigerant tomorrow.