NOTE For front differential integral housing servicing procedures see Front Integral Housing article

Automatic Disconnect Differential (ADD) allows engagement of front differential from 2WD to 4WD while vehicle is moving. On vehicles with ADD, a flange is mounted on the front hub which is splined onto axle shaft connected to side gear shaft on front differential. Locking hubs are not used with ADD.

When transfer case is shifted into 4WD, ADD is shifted into 4WD by operation of ADD actuator electric motor. ADD actuator engages clutch sleeve with intermediate shaft in front differential and side gear shaft, providing 4WD operation. When vehicle is in 4WD, an indicator light on instrument panel will be illuminated.

Operation of transfer indicator switch or 4WD switch completes ground circuit which allows ADD relay to operate. When ADD relay operates, voltage is supplied to ADD actuator for 4WD operation. See Fig. 1 , Fig. 2 Fig. 3 or Fig. 4 .

2001 DRIVE AXLES Differential - Automatic Disconnecting Differential - Front

Electric Cylinoydes For Sequoia Toyota
Fig. 1: Identifying ADD Component Locations (4Runner) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

2001 DRIVE AXLES Differential - Automatic Disconnecting Differential - Front

Toyota Sequoia Differential Diagram
Fig. 2: Identifying ADD Component Locations (Sequoia) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

2001 DRIVE AXLES Differential - Automatic Disconnecting Differential - Front

Indicator Engine 1kz
Fig. 3: Identifying ADD Component Locations (Tacoma) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

2001 DRIVE AXLES Differential - Automatic Disconnecting Differential - Front

2001 Tacoma Front Differential
Fig. 4: Identifying ADD Component Locations (Tundra) Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

Don't pay hundreds of dollars to find out what is wrong with your car. This book is dedicated to helping the do it yourself home and independent technician understand and use OBD-II technology to diagnose and repair their own vehicles.

Get My Free Ebook


Post a comment