From memory, both Rusty Dobro and Liz are correct. When Fergusons first came out to Australia (in the 40s?) they were grey. They had what was technically known as a wet-sleeved-cylinder motor (so you could replace the cylinders without replacing the whole engine block) the same as a Standard Vanguard (a uniquely shaped robust car popular in Australia at the time. I don't know any songs about Vanguard cars but I remember my grandfather's Fergie in South Gippsland (Arawata, near Korumburra) and learning to drive on it. It ran on a mixture of kerosene (what Poms call "paraffin")and petrol (what Americans call "gas") but others ran on either straight petrol or straight kerosene.

Ferguson in Australia were later taken over by Massey and the tractors were subsequently called Massey Ferguson (and I can't remember their colour but it may have been grey or red)but the grey Fergies were the ace and deuce of tractors for cockies (what Americans call "small-holders" I think)and are now collector's items.

Peter Pentland's repertoire was wonderful and I wish I could sing his Mallee Sheep Crutcher as well as he did. Whenever I drove back to Melbourne along the Calder Highway at night and got my first view of its lights as I came over the Pentland Hills Peter's songs would always stir my memory.