I just purchased a used Atlas GP9 locomotive from a reputable online shop. It was advertised as DCC equipped. When I set it on my track to try it out, it wouldn't run. Lights on, but would not run. Well, I wasn't pleased, but instead of calling the dealer and ripping into him,, I decided to sleep on it. Good thing. This morning it dawned on me (see what I did there, LOL), that being how it was a used loco, I would need to reprogram the loco (didn't think of this immediately as I am new to DCC and I have only run new locos one at a time on a layout that is still under construction). Change the address of the loco and voila good to go. The loco ran very well, but it was very noisy. After a search on this forum I took some suggestions, disassembled the loco and checked everything out, then put it back together. It now runs very much quieter. I was very pleased with myself. So, what is the problem? The truck assemblies are very loose and sloppy. One doesn't want to stay in. It falls out too easily. I need advice on where to find replacements. I scoured the Atlas site and found nothing. Googled my fingers raw today, and still, nothing. can someone suggest where I might look? Or, are there other brands that might work as replacements? Thanks.