2001 Subaru Impreza Owner's Manual - Page 196

Rear viscous limited slip differential (For RS models) D Never start the engine while a tire on one side is jacked up, as the vehicle may move. D If one rear tire is spinning in mud, avoid continued spinning at high speed as this could adversely affect the LSD. D If a different size rear tire is temporarily used (as in an emergency), it will adversely affect the LSD. Always replace it with a regular size tire as soon as possible. The LSD provides optimum distribution of power according to the difference in revolutions between the right and left rear wheels that may be caused by certain driving conditions, thereby improving driving stability on snow-covered, muddy or other slippery roads. CAUTION Steering J Tilt steering wheel WARNING Do not adjust the steering wheel tilt position while driving. This may cause loss of vehicle control and result in personal injury. 7-26