This is the product recommended in a La Mesa Model Railroad Club video for lubricating truck journals:
It is powdered Teflon in a liquid carrier.
The La Mesa Model Railroad Club operates the very large Tehachapi Loop layout at the San Diego Model Railroad Museum. They are fanatical about rolling stock performance.
If you cannot find this product at your local big box retailer or hardware store I recall the person in the video clip saying this product was available at lock-and-key shops.
I’ve used it for truck journals with very good results. I spay the Teflon into a small container (such as a shot glass) and apply the liquid to the journals with a microbrush. You do not need to remove the wheels. The liquid carrier quickly evaporates, leaving the Teflon in place.
There are similar graphite products that work the same way.
The video clip from the La Mesa Club is on this link: