TCU - Transmission Control Unit"A transmission control unit or TCU is a device that controls modern electronic automatic transmissions. A TCU generally uses sensors from the vehicle as well as data provided by the Engine Control Unit to calculate how and when to change gears in the vehicle for optimum performance, fuel economy and shift quality."
~Wiki
It doesn't really grind my gears, but I had to take advantage for pun's sake, and thought some of you could relate.
