(Injector Puller 6778 Kent Moore J-44639 For 2001~ 2004 GM Duramax 6.6L Steel. 3) Replace OTC 6778 and Kent Moore J-44639. Works on 2001~2004 GM Duramax 6.6L Engines. 1× Injector Puller. Simply insert the tool into the injector retainer bracket bolt hole.