This is my last K4 that I had running. It is a HO non DCC Spectrum cab numbered 5475. It will move forward and reverse with no problem but the shell moves side to side. I can not see any any problems with the side rods moving wrong. Any help would be appreciated .
Is the shell the only thing moving, or is the whole locomotive moving?
In general, you want the whole locomotive to move 😂😂.
It is the whole engine not just the shell.
Put a video up
Sounds to me like the wheels need to be re-gauged. If it's wobbling between the rails then
the gauge is too narrow. Spread the drivers.
HTH
Ken