2000 Toyota Tundra Owners Manual - Page 103

TUNDRA (34413U) (b) A.D.D. (automatic disconnecting differential) See "(c) Shifting procedure (button type)" for further instructions. The A.D.D. can be engaged or disengaged by the shifting operations described in "(c) Shifting procedure". You should drive in four- wheel drive for at least 16 km (10 miles) each month. This will assure that the front drive components are lubricated. Type A Type B 103