Not been able to get a photo but here goes. Just back from holiday in the car, done around 1400 miles in total. I noticed before our return journey that the oil level had dropped probably 1/4 of the way between max and min so maybe 250ml. On closer inspection there’s loads of spatter on the inside of the chassis rail which definitely wasn’t there previously and seems to have been chucked around by the aux belt. 
 

The thing is that the texture and colour of this is more like grease when rubbed between fingers and the patch I cleaned off is still clean as a whistle 400 miles later, whilst the oil level has dropped slightly again. 
 

Has anyone encountered similar? I’m wondering if it’s possible for something to have been splashed up into the aux belt given all the undertrays etc.

 

Ideas very much appreciated!

one thing to consider is the CV joint boots. Double check they're sealed and intact.

 

Had one of those go pop on my old fiesta and it coated the engine bay and underside of the bonnet with a lovely thick grease. Grey in colour if my memory serves me correct.