Lots of trial and error with the micro pro diffs. Build it as per instructions and put some toothpaste in it. Spin it with a low speed drill to break it in. Take it apart and clean everything. Build it again as per instructions and put in the oil of choice. Spin it to see how it feels. you can move shims from the inside of the diff to underneath the bearing. It may take a few builds to get it just right. If you plan on running both gear diffs, put the micro pro in the front with 80k and run the spec-r in the rear with 30wt shock oil.
Team EAM // Gravity RC