Documentation/Engine/Units/accessory transmission data

The accessory_transmission_data unit class is used to define the transmission characteristics for the player's vehicle, as well as the differential ratio. Units of this type are usually defined in /def/vehicle/truck/<make.model>/transmission/*.sii and valid unit names end in .transmission.

Attributes

Many common attributes are inherited from accessory_data.

Name	Type	Default Value	Description
stall_torque_ratio	float		This defines the maximum torque multiplication of the torque converter for an automatic transmission. The torque output of the transmission is clamped to a maximum of (engine torque × gear ratio × stall_torque_ratio). That is, the output torque stops increasing once the output speed drops below (engine speed ÷ gear ratio ÷ stall_torque_ratio). If unset, the transmission behaves like a conventional transmission without a torque converter.
differential_ratio	float		This defines the differential/final drive ratio between the transmission output shaft and the wheels.
retarder	uint	0	The number of output levels for the retarder if applicable. If zero, retarder behavior is disabled for the transmission.
ratios_reverse	float_array		This defines the reverse gear ratios in order of decreasing gear reduction. The values should be negative. Example: ratios_reverse[0]: -11.002 ratios_reverse[1]: -8.875
ratios_forward	float_array		This defines the forward gear ratios in order of decreasing gear reduction. The values should be positive. Example: ratios_forward[0]: 11.32 ratios_forward[1]: 9.132 ratios_forward[2]: 7.207 ...etc...
transmission_names	owner_ptr		Points to a unit of the type transmission_names, usually nameless and within the same unit definition file or included from a Serialized Unit Include (.sui) type file. This is used to assign custom names to each gear in automatic and sequential modes (these are overridden by h-shifter pattern definitions).