Rustyrails,
didn't take the comment wrong, figured you meant that since it was a present that it might be difficult to return. I am going to take all the suggestions and return it for repairs. thanks everyone.
justmom

Thanks for your suggestions. We tried both and the train still comes off the track at the curve. It is new, started coming off the track the very first time we tried to run it. It is the back wheels of the engine and the back wheels of the coal tender that come off when going around the curve. Speed doesn't matter, he can have the train going 40, 20 or even 60 and it still happens.

My son received this train for his birthday and the wheels will not stay on the track when going on the curves even at the slowest speed possible. How do we fix the problem. We are using the track that came with the train set.