I always love this topic. As someone in PM, I could never understand why a water resistant industrial grease with anti-seize needs to be used on a model train.
All you need is something for modeling purposes..not a heavy packing grease for 18 wheeler axle bearings.
For plastic to plastic gears, Tamiya R/C Ceramic or Cera HG grease. For metal to metal gears, try Tamiya Molybednum grease.
The gear material, speeds, pressures, temp., etc. that these greases have been engineered for, is identical to our O gauge trains.
For oil, the synthetic Liquid Bearings found on eBay is exceptional product.