I have a 1997 Dodge B2500 Maxivan with a 318 V8. The problem I'm told is that the a/c is not working this year. I took it to a shop - to have it checked out to see if it need refrigerant added - it worked fine last year, the van/air comes out but it is just cool. Well I was told that they could not check it because the lines were rusted and that it would cost $300-$500 to replace the lines. Any advice to fix this problem - or should I try another auto shop. Thanks