Float shifting

Float shifting or floating gears, also called "slip shifting", "dead sticking" or "bang shifting", is the process of changing gears, typically in a non-synchronous transmission, without depressing the clutch. Shifting in this manner is also used with synchronous manual transmissions, particularly after a clutch failure, to prevent destroying the syncromeshes with the power of the engine.

The most skillful drivers can shift non-synchronous transmissions without using the clutch by bringing the engine to exactly the right RPM in neutral before attempting to complete a shift. If done improperly, it can damage or destroy a transmission. Some truck (lorry) drivers use this technique with the higher gears when at work.

Technique

To upshift, the driver should first bring the engine up to speed. They must then shift to neutral and apply moderate pressure to the gear stick, and when the RPMs are low enough, the shifter will slide into place. The same technique for shifting down is used except that the accelerator must have some pressure applied to it to bring the RPMs up to match the speed of that gear at that wheel speed.

Use in emergency scenarios

Float shifting can be used in the event of a clutch cable or clutch pedal failure, as it allows a skilled driver to drive to a service location. The transmission is switched to neutral, and the engine started. The transition to forward motion is achieved by pressing the shift lever into the first gear position with force, in order to use friction to transmit torque, moving the vehicle. This is extremely damaging to the shifting hardware, and is used only in dire situations. Once the engine is shifted into first gear, upshifts are be done by feel, as described above.