Oil-filled Gear Differential

The all-metal differential is built to last with four spider gears, and a combination of gasket and O-ring seals allow diff action to be tuned with oil. This is usually the part where we say, “but the diff arrives greased from the factory.” Not this time. Losi went all the way and filled the diff with oil. Listen brands—if you’re gonna bother with a sealed diff, be like Losi and put oil in it.