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Published with permission from the Federation Internationale de l' Automobile.

ARTICLE 9: TRANSMISSION SYSTEM
9.1 Transmission types:
No transmission system may permit more than two wheels to be driven.
9.2 Clutch control:
9.2.1 If multiple clutch operating devices are used, they must all have the same mechanical travel characteristics and be mapped identically.
9.2.2 Designs which allow specific points along the travel range of the clutch operating device to be identified by the driver or assist him to hold a position are not permitted.
9.2.3 The minimum and maximum travel positions of the clutch operating device must correspond to the clutch fully engaged normal rest position and fully disengaged (incapable of transmitting any useable torque) positions respectively.
9.2.4 Designs or systems which in addition to typical inherent hydraulic and mechanical properties are designed to, or have the effect of, adjusting or otherwise influencing the amount, or rate, of engagement being demanded by the FIA ECU, are not permitted.
9.3 Traction control
No car may be equipped with a system or device which is capable of preventing the driven wheels from spinning under power or of compensating for excessive throttle demand by the driver.
Any device or system which notifies the driver of the onset of wheel spin is not permitted.
9.4 Clutch disengagement :
All cars must be fitted with a means of disengaging the clutch for a minimum of fifteen minutes in the event of the car coming to rest with the engine stopped. This system must be in working order throughout the Event even if the main hydraulic, pneumatic or electrical systems on the car have failed.
In order that the driver or a marshal may activate the system in less than five seconds, the switch or button which operates it must :
- face upwards and be recessed into the top of the survival cell no more than 150mm from the car centre line ;
- be designed in order that a marshal is unable to accidentally re-engage the clutch ;
- be less than 150mm from the front of the cockpit opening ;
- be marked with a letter "N" in red inside a white circle of at least 50mm diameter with a red edge.
9.5 Gearboxes
9.5.1 A gearbox is defined as all the parts in the drive line which transfer torque from the engine crankshaft to the drive shafts (the drive shafts being defined as those components which transfer drive torque from the sprung mass to the un-sprung mass). It includes all components whose primary purpose is for the transmission of power or mechanical selection of gears, bearings associated with these components and the casing in which they are housed.
9.5.2 In this context the following parts are not considered part of the gearbox and may be changed without incurring a penalty under the F1 Sporting Regulations. If changing any of these parts involves breaking an FIA applied seal this may be done but must be carried out under FIA supervision :
- the clutch assembly and any shaft connecting the clutch to the crankshaft or first motion shaft of the gearbox, provided this is located prior to any mechanical speed reduction from the engine ;
- the clutch actuator and clutch release bearing(s) ;
- inboard driveshaft joints and seals but not their housing if that housing is integral with the gearbox output shaft and therefore part of the sprung mass ;
- the hydraulic system prior to the point at which it produces direct mechanical movement of the gear selection mechanism by means of hydraulic actuator(s) ;
- oil, oil pumps, oil filters, oil seals, oil coolers and any associated hoses or pipes ;
- electrical sensors, actuators, servo valves and wiring ;
- any parts associated with the suspension or functioning of the sprung suspension that are attached to the gearbox casing ;
- the rear impact structure provided it can be separated from any gearbox casing ;
- any other component mounted to the casing whose primary purpose is unconnected with the transmission of power or selection of gears.
9.6 Gear ratios :
9.6.1 The maximum number of forward gear ratios is 7.
9.6.2 No forward gear ratio pair may be :
- less than 12mm wide when measured across the gear tooth at the root diameter or any point 1mm above or below the root diameter. Above this area each side of the gear teeth may be chamfered by a maximum of 10°. In addition, a chamfer or radius not exceeding 2.0mm may be applied to the sides and the tip of the teeth ;
- less than 85mm between centres ;
- less than 600g in weight (excluding any integral shaft or collar). If an integral shaft or collar is to be excluded the mass of this may be shown by calculation assuming the gear to be 12mm wide and the shaft geometry to be the same as that where slide on gears are used.
9.6.3 Gear ratios must be made from steel.
9.6.4 Continuously variable transmission systems are not permitted to transmit the power of the engine defined in Article 5.1.
9.7 Reverse gear :
All cars must have a reverse gear operable any time during the Event by the driver when the engine is running.
9.8 Torque transfer systems :
9.8.1 Any system or device the design of which is capable of transferring or diverting torque from a slower to a faster rotating wheel is not permitted.
9.8.2 Any device which is capable of transferring torque between the principal axes of rotation of the two front wheels is prohibited.