2000 Dodge Intrepid review from North America

My motor blew out at 35,000 miles. When I took it to the dealer to look at first they said they needed to open the motor up to get a better idea of what was wrong and they did and told me that I didn't change the oil which I did in a timely manner and always took it to the dealer service department to change the oil. They told me that I would have to pay for a new motor and of course I declined because the car is not even paid off and only has 35,000 and the oil was always changed at 3,000 miles or every 3 months. They gave me a customer service number and the representative read my file and the service department has written in it that I had sludge in my motor (not what they told me) so I informed her that they told me different so she said to get the district manager's number from them, but of course they refused. I am still waiting for something to be done about my car. They said the district manager would call me, but still no call. I have no idea what I can do about this problem.