@Trainlover9943 posted:Thanks. Could I still run it or should I not until I fix it? Would the Lionel trucks be compatible? What should I do? I believe I have some spare freight car wheels but I doubt that'll work.
Anything is compatible if you have the time and skills to make it compatible. K-Line trucks were made for K-Line cars, Lionel trucks for Lionel cars and MTH/Williams for MTH/Williams cars. You can make the trucks fit with a bit of jury rigging. Have you taken any heavyweight car apart? Can you solder?
You could cut the axle of the middle wheelset and remove the wheels. There is nothing wrong with running a heavyweight three axle truck without the middle wheelset. John