2004 Subaru Outback Owner's Manual - Page 302

Starting and operating Rear viscous limited slip differential (LSD) (if equipped) UB7037BA 4. Insert the screwdriver into the hole. 5. Push down on the screwdriver, push down the button and move the selector lever from the "P" to the "N" position. 6. Remove the screwdriver from the hole. Depress the brake pedal and start the engine. Take your vehicle to the nearest SUBARU dealer immediately to have the system repaired. Never start the engine while a tire on one side is jacked up, as the vehicle may move. If one rear tire is spinning in mud, avoid continued spinning at high speed as this could adversely affect the LSD. 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. - CONTINUED - 7-29