All of our new parts are aftermarket replacements. Compatible with Ford Backhoe Loader(s) 1871. Compatible with Ford Construction & Industrial(s) 1801, 1811, 1821, 1841, 1871, 1881. Compatible with Ford Engine(s) 172 (diesel). Compatible with Ford Tractor(s) 800, 801, 811, 821, 841, 851, 861, 871, 881, 900, 901, 941, 951, 961, 971, 981, 1811, 1841, 4000. Compatible with New Holland Hay Cutting(s) 907, 909. Replaces Ford OEM Number(s) 3A50FS. Contains all gaskets necessary for a complete engine. All States Ag Parts Item No.