Hello,
I have 5 post war Santa Fe F3 Diesels. The problem is that they each run at different speeds. 1 runs very fast, 1 runs at what I would say is normal, 1 runs slow, 1 runs very slow, and 1 has a problem of the front motor is slower than the rear motor. I have a ZW transformer that I believe is working properly. I do not have any voltage drop in the track. All of them have the same grease in the worm gears. I can not operate 2 at the same time because one is stronger than the other resulting in a derailment. The one that operates normally has the most use of them all. The very slow one looks showroom new inside and out. The speeds are the same in forward and reverse. What if anything can I do to get them a little more consistent to each other.