4x4 not working

[Travisbsmith]

I have a 1996 Tahoe, it has electronic 4 wheel drive. I attempt to put it in 4hi or 4lo and the lights just keep flashing. I can hear the transfer case switching but will not engage the front end. I've changed the front end actuator 3 times with used ones. I couldn't help to think all of them were bad,so I took one and hooked it up to my battery. It moved out,but very slowly. I need help, we are supposed to get at least 3 inches of ice in the next couple if days,and I will need my 4wd

 

[lesterl]

You can buy a special bolt that keeps the front end locked in all the time IIRC....

Now, there is an encoder on the transfer case, you shure it is working properly? There is an electronic control module on a bracket on the steering column also..... Check wiring, PRNDL switch on transmission (Has to be in park/ neutral - or at least see/detect it.) Also the Dash switches have been notorious for failure IIRC.....

Good luck.... Also like 4 fuses......

 

[Travisbsmith]

I've replaced the switch,and the transfer case control module today. It acts like it goes into 4wd,just the front end is not engaging. You can feel the gear ratio change,also you can hear the u joint on the front end make a little noise when switching from 4hi to 4lo in neutral

 

[lesterl]

You been putting in a NEW actuators or J/Y ones?

 

[Travisbsmith]

Got my 4x4 working,turned out to be the "transfer case vacuum switch" located on top of the transfer case. I work at a salvage yard so I had access to a brand new switch, I'm glad I didn't give up. :happy160: