THE 406 HDi is available with either four-speed automatic or five-speed manual transmission. The automatic gearbox is electronically controlled and offers a choice of sport or normal operation modes. The manual gearbox uses a heavier, 500-gram counter-balancer to minimise noise and vibration, and the hydraulic clutch uses a "pull" mechanism in V6 and turbo-diesel ML series. The manual clutch pedal assembly has a thrust stop 25mm from the end of travel to ensure de-clutching.