Open Differential. When the driving wheel of the car revolves, the outer wheel is always turning faster/more than the inner wheel on cornering. This is due to the final gear acting as one unit, with the special structure which utilizes the four bevel gears which are facing two gears which are connected to both left and right axle side gears (the differential) known as the other two pinion gears. When the car accelerates forward the final gear and the whole differential acts as one, it turns both left and right axles at the same speed. But normally when cornering the revolution & speed of both side gears left and right changes due to the way the pinion turns, this causes the differential mechanism to force the outer wheel to turn faster than the inner wheel.

Limited Slip Differential. Also known as the nonslip differential, L.S.D. When the wheel on one side of the driving wheel enters into mud or when it loses grip, that wheel would usually idles due to the function of the open diff differential gears, thus making the car unable to move. This is due to the difference of rotating speeds of both the left & right side drive shafts (being different in motion) is restricted depending upon when to lock. There is with a friction plate type LSD which utilizes gears and clutch plates to generate differential resistance and then there is an RPM response type LSD which utilizes rotary difference. The friction plate system furthermore is classified into residual pressure type "multiple plate type" for torque proportional systems.

Viscous LSD works by utilizing plates within housing with thick fluid. This LSD works by sensing the rotation speed between the 2 drive shafts. The 2 sets of plates are connected to a driveshaft on one side. Normally the driveshaft’s and fluid will spin at the same speed but if one side changes speed the fluid stuck between the plates will try to catch up to the faster side by transferring the torque to the slower side.


Torsen LSD units are purely a mechanical design and don’t use any viscous fluids, plate clutches or electronically devices. This design operates on its internal worm like gears & consists of the combination of 3 types of gear, 2 worm gears which is connected to the left & right drive shafts (those which are suitable with side gears of the normal diff). This works similar to the open differential but when one wheel looses traction the worm gears then bind or lock together which in effect will force both sides to run at the same speed. The key points in this design are the internal gears and their design as it will determine its torque bias ratio. This type is more commonly popular with higher powered all wheel drive cars. TORque SENsing is the meaning behind the name of TORSEN.


The Technical Trax LSD unit is based on the multiple plate clutch design. With this design the multiple friction clutch plates are located between the side gears and the differential casing and utilize the pinion and cam gears. This is a torque proportional type LSD. In the usual differential arrangement it is connected to both left & right axles directly, when the driving force of one side differs in speed the pinion gear with the cam angle forces the clutch plates to compress and grip to in effect transfer the driving torque evenly to both axles. The T-TRAX ADVANCE has adopted this system which has proven its effectiveness as the best for 2WD applications.


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