[magman]

As far as the noise w/the gears..all metal to metal gears make a lot more noise than plastic to metal. All of my trucks have metal to metal w/no issues and no lube. I am running mod 1 pinions from RCMonster..

The trans can be lubed with red bearing grease, white lithium grease...either will work nicely. Or you could put STP in there and use that. This process is messy and requires you to drill a small hole to insert the lube into and install a rubber plug. I did this on my Revo and it did work...again, it is messy and the oil does leak out unless you seal the trans with something like gasket sealer or black RTV.