For those that are curious about what kind of motor oil an M4 Sherman used, maintenance manuals can be downloaded in pdf format at another site relating to the Army’s habits of automotive maintenance: http://www.delbertsscalemodels.com/DSM/index.php/reference/downloads/viewcategory/11-wwii-military-vehicle-manuals…
The original thread is here: http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3361313/1