Ford Tractor 172 Diesel Head. Head for Ford diesel tractor with 172 engine. I was inquiring about some tractor parts for sale, and told the guy I need a good 4000 head. Well, I didn’t specify I had a gas engine, and he didn’t tell me it was a diesel head, so I bought something I can’t use. I can’t really attest to the condition from my own experience, but he said it was a very good head. The other items I got from him were very good and as he described. Head comes as seen in the photos. Should fit 1964, 1963, 1962, 1961, 1960, 1959, 1958 years, 4000, 801, and 901 models.