I think he's full of BS. If the dealer is being a jerk, I would go somewhere else. No need in giving him a dime if he isnt willing to work with you. When I was looking at new AV's ('04) a while back the dealer had Z-71's w/out sunroofs.
I wanted a Z-71 w/everything: leather, sunroof, etc. The salesman didnt want to show them to me because he said that since I was so young that he didnt think I would be able to get the financing for a $42K vehicle. I politely shook his hand, and told him "thank you sir, your probably right. I have never bought a vehicle before and I had no idea that lenders consider your age when you apply for a loan." As we were walking back towards the front of the lot I asked him "Even though I just graduated with a degree in Engineering and make $70,000, you really think they wont give me a loan?" His ENTIRE attitude changed. He said that he 'thought' he could make it work, for me to just fill out a little papework inside. I told him no thanks that I would go buy somewhere else.
Call some other dealers in your area. Good luck!
Zach