ADD System

[cmartin0013]

OK guys i have a 1996 4runner limited when i hit the button on the 4wd and lock it i can hear the xfer case lockin and feel it shift down but there are no 4wd lights coming on and the front wheels are not pulling. the only light thats comes on is when i hit the dif lock the abs light comes on. I wanted to delete the auto or add hubs w manual locking hub but found out its just not a simple bolt up after the year 1995 bummer any thing would help alot

[fourwd1]

The 4wd indicator lights when the ADD front axle locks and the t-case is in 4wd.
The front axle lock and unlock is done using Vacuum valves.
You could have a bad valve or vacuum line.
Start by getting underneath and checking the basic line connections.

And adding auto or manual hubs will not help with this problem.