Nice work here
Wow i really like this, theres alot to see here, i do however think you should add alot more "SHINE" but also give it some oil and greese thats around in spots, so a mixture of shine and greese would also give this more of a realistic look aswell, just an idea of improvment but what you do have here is very impressive and very detailed its a work of art that is very welldone indeed, and i praise you on this, anyways nice job all around here.
~~THINGS TO IMPROVE ON~~
I have suggested some shine and even mix in some oul and greese in there.