I am confused here. my new design lionel trucks with the thumb tack hanging down work on just about every car I own. the do not bind at all. they have some play when coupled to the older style coupler. I have 036 fastrack curves and switches and the cars do not derail at all. obviously I do not have the new design trucks with the hidden uncoupling tabs yet.
so my question is. is this problem everyone is having with the derailments and too tight a fit. limited to the new trucks with the hidden uncoupling tabs or both new designs?