That corn head grease is what's called thixotropic, meaning it liquefies when agitated. It doesn't take any real heat for that to happen.
The mud in Cook Inlet near me does that, which is why people can slowly sink into it and get stuck. Tossing a rock in will create a small crater with the rock at the bottom. I once had to climb up a rock covered road cut that was coated with mud. As I stepped on it and agitated the mud, it suddenly slid off the slope. Really weird stuff.
