Lionel is not taking non-warranty repairs, and they won't be taking any repairs for two months.
If you got it for a good price, see if you can extract a little more from the seller and then go about fixing it.
I have no doubts we can fix it, it doesn't sound like anything super expensive could really be wrong. If the trucks and motors aren't binding through a full rotation of the drive wheels, I see the motor is available, and I'm pretty sure I have all the electronics in stock for those.