Torsen Torque-Sensing (full name Torsen traction) is a type of limited-slip differential used in automobiles. It was invented by American Vernon Gleasman and manufactured by the Gleason Corporation. Torsen is a portmanteau of Torque-Sensing. TORSEN and TORSEN Traction are registered trademarks of JTEKT Torsen North America Inc (formerly Zexel Corporation, formerly Gleason Power Systems). All Torsen differentials have their origin in the Dual-Drive Differential that was invented and patented by Gleasman in 1958. Use Torsen differentials can be used in one or more positions on a motor vehicle: center—used to apportion torque appropriately between front and rear axles on an all-wheel drive vehicle. rear—used to apportion torque appropriately between left and right sides in rear axles. This may be on either a rear-wheel drive or a four-wheel drive vehicle. front—used to apportion torque appropriately between left and right sides in front axles. This may be on either a front-wheel drive or a four-wheel drive vehicle. A four-wheel-drive vehicle, for example, may use one, two, or three Torsen differentials. Types , there are three types of Torsen differentials. The original Torsen T-1 (Type A) uses crossed axis helical gears to limit torque split. The Type I can be designed for higher torque bias ratios than the Type II, but typically has higher backlash and the potential for noise, vibration, and harshness (NVH) issues, and requires a precise setup/installation. The later Torsen T-2 (Type B) uses a parallel gear arrangement to achieve a similar effect. There is also a specialist application of the T-2, known as the T-2R (RaceMaster). The latest Torsen T-3 (Type C) is a planetary type differential, in that the nominal torque split is not 50:50. The Type C is available as single or twin version; the Torsen twin C differential has front and center differential in the same unit. The Torsen T-3 is currently employed as the center differential in all non-Haldex Traction Audi models with a ZF-sourced automatic transmission Quattro four-wheel drive, such as: Audi A6, Audi A7, and Audi Q7. Audi uses a mechanical "Crown Wheel" center differential for all longitudinal implementations using dual-clutch transmissions, such as the 2013/14 S4/RS4. Alfa Romeo used a Torsen C twin differential in the Alfa Romeo 156 Crosswagon Q4 and also in the 159, Alfa Romeo Brera and Spider Q4 models. Also, Toyota uses a Torsen T-3 in the center differential of the 4Runner Limited, FJ Cruiser 6-speed manual, Land