E46 ZF Slave Cylinder

A common source of transmission problems

Your BMW's clutch slave cylinder is attached to the side of the transmission and transmits pedal movement to the clutch with hydraulic pressure. With age the seals can fail from corrosives. Normally if a slave cylinder is failing it will become difficult to shift due to poor clutch engagement. If the slave cylinder fails the pedal will go all the way to the floor and not come back.