stock 4X4 system not working

My 1997 Tacoma stock has automatic 4X4 hubs and when I shift into 4HI or 4LOW the drive shaft spins but no action from the wheels and the little 4X4 indicator light does not come on the dash. I have new axles and there is NO metallic or grinding noises coming from the system I have not been abusing or going off road with the truck.
Does anyone have an idea what could be the problem?

 

actually the first gens do not have automatic hubs. the hubs do not disconnect the differential does. check the vacuum lines running to the actuator. its on the passenger side of the diff. 2 lines running to it. make sure they are in good shape and not torn or have holes

 

Thanks I will look into that I appreciate the help.

 

You have to get out, and lock the hubs.

 

First gen is 1995 – 2004? They are not the manual hubs. They are full time hubs I don’t have to get out. I just shift and there’s no buttons to press. If it is the vacuum lines would that keep the 4X4 light on the dash from coming on?

 

pre 2000 add or automatic disconnecting differential was optional. 2000 and after got add. and it could because the computer wouldnt see the system fully engaged

 

wrong. some you do some you dont

 

Thanks I’m hoping it’s that ADD actuator and not some internal problems I appreciate the help.

 

Check all the vacuum lines. You can also get a vacuum pump and try to manually engage it. Sometimes it will stick and wrapping on it with a hammer with free it up!

robert

 

Problem solved it was the ADD actuator. I took it off tested the OHM’S, test was unsatisfactory I got a new ADD actuator for about 85$ and I’m good to go I appreciate all the help and input .

 

was yours vaccum or electric? or is the electric selinoid in the actuator?