I've been having issues with Walther Horizon commuter cars. normally i run the commuter type (NJT), but i bought undecorated Amtrak versions with different trucks. At first i thought it was the trucks bumping the side details (and they do) but it doesn't seem that the trucks are the problem anymore. I think my track somehow warped or got out of gauge. i know for a fact on one end there are 2 or the dips in the rails, and cars roll right off. there are also places where one wheel seem to stay where it should be, but the other rolls up on top of the rail and derails. most surprisingly, of all the track i used on my layout ( most of it old stuff) its the newer 22" curves on the outside with these problems. the other end of the layou on the 22" curves is doing the same thing, and now it s more apperent. I used to just think my Challenger was a litle off, as the front pilot would derail their alot. now these passenger cars do to, and when i try to roll them over, there is a grinding sensation at that area, and sometimes the cars even with the weight of my hands still jump the tracks. confusingly, my other rolling stock and locomotives seem to be able to take all of these bent and warped rails fine, but there is definitely something wrong. still , i'm not entirely sure if it is the curves either. i need to get a track gauge. does anyone know whats causeing these derailments?