Here's what Lionel's online ad says (from their site):
For even more excitement, add a baggage car, a diner, and a hot chocolate car to complete your Polar Express train.
That to me says the engine SHOULD be able to pull the complete train.
The comments to add another engine, that's the way it's always been (tradition is not always a good thing), Lionel had no idea that...(WHAT?!?!?!) are not what someone who has a problem wants to hear. Spending more money is also NOT what someone wants to hear.
Send the engine in for servicing, if it still won't pull the "complete" train, ask for (all) your money back.
If this was anything else than a toy train people would be up in arms about it.
