limited-slip differential is the instead of the vehicle's power shifting from front to rear when the vehicle's electronic Control unit senses wheel slipage (which is what four-wheel or all-wheel drive does), the limited-slip differential works from side to side.
If the right wheels drop off the road in a low traction situation and begin to slip, power is transferred through a viscous (thick liquid) coupling unit to transfer power to the left wheels, where there is better traction.
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