Monaco RC has presented a Diff Check Tool for setting up and controlling the hardness of differentials for 1/8th and 1/10th scale cars. Diff Check provides data to the drivers that allows them to evaluate or replicate a certain hardness, so you no longer risk losing the required level of hardness by topping up the diff oil.
With this tool, drivers will have a record that allows them to choose a softer or harder diff. Diff Check is useful for all categories and scales that use oil diffs.