Originally Posted by TeamThibault
how do you build your diffs?
With my gear diffs I do a couple of things to ensure they don't leak.
Coat both the small o-ring seals and the gear case seal with 3 racing anti wear grease, this helps to make a leak free seal when the seals are squeezed into place, and helps to keep the small o-ring seals lubricated so they don't wear & leak.
Before assembling the diff casing, screw the small screws into the 4 holes on the larger half of the diff case and then remove the small screws.
When this is done you'll see that around the holes the plastic has raised up a little, with very fine sand paper on a flat surface, sand the face of the gear case with the holes until the bumps are gone and the face is flat.
Don't over fill the diff, only fill until the oil is level with the top of the cross pins that hold the smaller gears in place. This will prevent over pressurizing the diff and stop it leaking.
If any grease seeps up from the screw holes when putting the 2 halves together don't worry as this will also act as a seal around the screws when they are put in place and tightened up. Don't over tighten the 4 small screws as this will make the diff bind and distort the center seal causing it to leak.
If you follow this procedure along with what the manual says, you should end up with properly functioning diffs that won't leak and will last you a long time.