Limited%20Slip%20Differential

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Limited Slip Differential

• By Khashayar Toutounchian
• Instructor Kevin Cedrone

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Why you need a differential

• Car wheels spin at different speeds, especially
  when turning.
• Wheels would have to be locked together, making
  turns difficult on the car.
• Differential transmits the force through the axle
  from one wheel to another to prevent slippage of
  a tire

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Limited Slip Differential (LSD)or Positraction

• Uses various mechanisms to allow more torque to
  be transferred from a slipping wheel to the
  non-slipping wheel.
• Clutch-type LSD has the same components as an
  open differential, plus a spring pack and a set
  of clutches.

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How LSD works?

• Clutch packs inside the differential create
  additional resistance. The resistance is always
  present.
• The tire has to overcome the traction present
  plus the preload resistance to spin faster.
• Traction and preload have to be high enough to
  keep tires from spinning but low enough to still
  allow tires to rotate at different speeds in a
  turn.

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How useful is LSD?

• LSD limits the slippage but doesn't prevent it.
• It works in easy off-road conditions or on mildly
  slippery roads, but for serious slippery or
  off-road use its not powerful enough.
• References
• http//4wheeldrive.about.com/cs/offroading101/l/bl
  ltdslipdiffs.htm
• http//auto.howstuffworks.com/framed.htm?parentdi
  fferential.htmurlhttp//www.automotive.eaton.com
  
• http//www.4x4abc.com/4WD101/limitedslip.html
• http//auto.howstuffworks.com/differential8.htm