Mine had black oil dripping from the lower oil cooler hose. The whole lower left front of the engine compartment was grungy. The compressor was well oiled as was everything else down there. I was certain that the source of the leak was the lower oil cooler hose.
Well, guess what
? It was PS fluid sweating through the low pressure PS hose. The PS fluid would pick up the black coloration as it mixed with the overall black grunge on everything in that area. Thing is, the PS hose itself never appeared damp. Sure fooled me, but, anyway, it's fixed now.