What is the M Differential Lock and how does it work?
The M Differential Lock, fitted as standard equipment to every E46 M3, is an advanced version of the traditional limited slip differnetial. Though still entirely mechanical in operation, the M Differential Lock is activated when there is a difference in rotational speed between the two rear wheels. This difference pressurizes a viscous silicon fluid, which then operates a multi-disc clutch that directs more power to the wheel with the greatest traction.
