gp100

I just use a little bit of black Moly Grease made for R/C..

I don't go overboard with it, but just enough to lubricate the metal gears here and there.. I believe it's better to have some lubricant on a gear, rather than run them dry..

Moly Grease stays where you put it for the most part, and doesn't splatter everywhere like an oil might.. And when you have sensitive electronics sitting that close to a gearbox, the last thing you need is oil getting on electronics.. Not a good idea.. Hence why I say grease is a far better option for a gear set..

Doesn't have to be Moly Grease.. Any grease that is plastic compatible is a good choice.. This way you lube the gears, but it won't damage any plastic parts in the tank if it does manage to get on anything else..

Even metal gears require some lubrication against wear from time to time..