Knowing your diff viscocity is vital. As your diff oil gets older and a new diff breaks in, it changes viscocity. Ambient temperature plays an even bigger role in diff viscocity changes. A diff in the morning will feel stiffer than a diff in the middle of a hot day. This is why the SkyRC diff checker is vital. Know what your diff measures when the car is at it’s best allowing you to replicate diff viscosity day in, day out. Available now at www.superstockrc.com