Almost has the consistency of gasoline.. smells terrible too. The 'PTFE' in the label is basically teflon. I looked up the wikipedia page and it looks like PTFE is also used in bearings so I guess it's the right stuff?
https://en.wikipedia.org/wiki/PolytetrafluoroethyleneMy guess is that it's probably the old original oil/lube re-gumming up over time..