It's based on this book:
http://www.amazon.co.uk/The-Tank-War...8DSAKZQ12ZEA2A
Im not sure why they had to make a fantasy movie like Fury when the story in that book is real and doesn't have to resort to cliche, inaccuracies or just plain making stuff up. It's also far more emotionally charged and frankly a really sad book. It would have made a much more poignant film about war. It even has Shermans in it, Fireflys at that.