Back in the 70's when I had a Morris Marina I used to paint the underside of the car with old engine oil to stop the rust. It worked OK until one weekend some friends came to stay with their little white Scottie dog who used to root around under the cars and they wondered why his head and back had suddenly turned black. We used a lot of washing up liquid that weekend. I did suggest Gunk but that didn't go down too well.  3 x FL1 2 manual + 1 auto
5 x FL2 4 manual + 1 auto
Now Discovery Sport P250 MHEV SE