4wd won't engage

I have 96 tacoma manual hubs and 4wd shifter but when trying to engage the 4wd light comes on but won't engage . When trying to shift into 4lo it stays in nutrual ...and yes I've locked in the hubs

 

Probably something to do with the two vacuum lines. For some reason it seems to pop up often in our earlier models (95-97). Thats where i would start. Luckily our system is very basic and by the light coming on it basically leaves you with the one possibilty. Theres a few posts on here that helped me diagnose a similar problem.

 

Yup. Check the vacuum lines running between the actuator and diff. They could have the smallest of pinholes that you can't even see that'll make you pull your hair out. Mine did this as I tried to leave the beach and I got the pleasure of being pulled off the beach and up the dune by a Chevy...

 

Always a sad day when a Chevy has to pull ya out. At least it wasn't a Ford lol.

 

No vacuum lines with manual hubs so forget that.

So when you put it in 4lo the vehicle won't move at all? If it was the hubs not engaging the truck would still move, it would just be in 2 low. The rear wheels would still get power. If this is the case then the issue is at the tcase. Are you sure your getting the shifter all the way into 4 low? Could be the shifter seat (bushing under shift lever) is worn out, this can cause the shifter not to shift properly not allowing it to go fully into gear.