There were some issues with the gear box. My first one went back to Lionel after less than one month because it would stall and the cab light would blink. It made 3 trips back and forth. Finally someone from Lionel called and asked if it was okay to replace it. The replacement lasted longer but still balks from time to time. A little push at startup will get it running.
The problem seems to be related to gear lash. You can rock the locomotive back and forth 1/4” to 1/2” when it is stopped. I would love to know what they changed and whether we could retrofit that change.