I have been running the Traxxas stock differential in the stock tranny case and another in a FLM case. Now that I have put my Diff n a new RPM gearbox, after a few runs I noticed that there is A LOT of grease coming out of the gear box at the axle shafts. It's the same black grease that's in my diff. Could this just be a leaking differential from age? It has never done this before. Or could it be that I put too much grease in the diff? Anyway, I plan on taking it out and seeing what's up.