Silverado Transmission

Chevrolet just placed a new transmission in my 2500HD Silverado. I was 2000 miles over the 36,000 mile warranty and thus Chevrolet won't help me out at all with the costs. The only thing they can tell me that was wrong with the transmission was that the fluid was black with metal in it, and therefore it was my fault. Is there any chance I can get anywhere with Chevy on this one or am I wasting my time. Thanks for ANY input or advice. Email -- [email protected]