2000 4Runner wont disengage from 4 wheel drive
Unlike older vehicles that you had to manually lock the front hubs on your vehicle has automatic locking hubs, the 4-runner has an eletronic motor on the front differential called an actuator that works very similar to how a window motor operates, if the 4x4 is not frequently used these motors go bad internally and tend to jamb, even if not needed it is a good idea to cycle the 4x4 in and out about once a month to keep this system operating, what is happening here is the front actuator is stuck and keeping the 4x4 engaged, sometimes you get lucky here and if you tap on the black electronic actuator on the front differential while having someone cycling the system on and off you can get it to start working again, if not then plan on replacing the actuator.
The actuator cost around $200