OK, I know this is an old topic, but I wanted to give a big thumbs up to this advice. In the last few weeks, I've been running my trains for the really first substantial period, ever. The 4-axle Atlas and 6-axle Kato units were very nice, but my pair of SD50s were complete dogs. They wobbled, stalled on frogs, derailed and even jammed up on the code 55 frogs. I was pulling my hair out and ready to find another hobby.
Strangely, I had measured the gauge of these locos with my MT coupler do-dad and they were consistently tight on all wheel sets. But until I read the instructions in this thread, I was at a loss as to whether I should take the trucks apart and do surgery. It was not clear that was the issue- how could it be so simple?
I can happily report that after about 10 minutes with a jewelers screwdriver, I widened all the wheel sets and both locomotives are reborn. They glide through turnouts at the slowest speeds, nary a hesitation. Even the wobble is mostly gone.
I'm a happy guy!
Thanks
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