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There are two types of these, a plate type and a gear type. Both generate friction to provide the limited slip effect.

To create friction in the differential pressure is applied to the plates by a spring, the amount of pressure can be varied by changing the strength of the spring. The pressure applied is determined by the amount of torque required to turn a side gear while the other gear is held static. We can adjust the amount of torque required to rotate a side gear to any setting, generally the range is anywhere between 30-90 LBS/FT and is dependent on what the car is used for.
In addition to this the friction in the plates can be made to increase when the car is moving. This is achieved, depending on the design and make, by the planet gears or the planet gear shafts moving up ramps in the cones when the car is accelerating or decelerating. By varying the angle of the ramp the friction in the plates can be altered. As an example a ramp angle of 30 degrees will increase the friction in the plates more than an angle of 45 degrees. The characteristics of the LSD can be altered for the type use and driving style. For example a driver may prefer a setting that gives maximum friction in the LSD under acceleration but no extra friction when decelerating. This would require cones with 35 degree ramps for acceleration and 90 degrees for deceleration. Another preference could be cones with a ramp angle of 45 degrees on both acceleration and deceleration. There are many combinations of ramp angles, we can advise on choice according to type of use and specification of car.

A useful feature of the plate type LSD for competition use is if one rear wheel loses contact with the road, as often seen in a racing and rallying during fast cornering, the drive is still transmitted to the other rear wheel to keep the car's speed going.

When operating, a plate type LSD can be noisy. When the car is turning a clonking sound is made, this is more apparent at low speed but is a normal characteristic.


The gear type LSD comprises helical teeth gears fitted into pockets inside the housing. When there is a difference in the loaded speed of the halfshafts, friction is created by forcing the gears against the wall of the pockets. Both wheels need good contact with the road when cornering to generate friction in the LSD and increase traction. The differential is silent in operation.

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