[Spridgets] Torque Sensing LSD

[derf]

To understand a viscous LSD or VLSD, picture a drum full of thick goop.
Picture the axles having tabs on the end like turbine fans.  As the turbine
fans rotate at different speeds, the tabs heat the goop by friction.  As the
good heats, it thickens.  So, the more the axles turn at different rates,
the thicker the goop and the more resistance against turning at different
rates.  If the axles turn at the same rate, the goop is less thick.
There is a better explanation somewhere online.  Let me see if I can find
it.