When I put my truck in 4x4 the 4x4 light on the dash comes on and the truck steers like it is in four wheel drive. If I get stuck while in drive only one rear wheel spins and the other three do nothing. If I shift into reverse only one front wheel spins and the other three wheels do nothing. Results are the same when in 4H or 4L. How do I get both axels working at the same time? Thanks.

 

Need to verify the CAD (central axle disconnect) is actually working. Normally, if the light comes on/goes off when you shift into/out of 4 wheel drive, it generally implies it's working..... but, it may not be fully engaging the passenger side axle, and that can lead to some odd behavior. Even so, if ONE front tire is turning, one rear tire should be too....

 

Ok other than checking the vacuum lines how can I verify it's working?

 

Jack up the front end. Run the engine at idle, and put the t-case in some flavor of 4 wheel drive. (leave the trans in park) Then try and turn the passenger front wheel by hand. You shouldn't be able to.

 

OK. I drove the truck down the street and put it in 4H the 4x4 light came on. I parked the truck jacked up the front end and started it up. I can easily spin the passenger side wheel both wheel spin easy but hand. I inspected the vacuum lines and they look ok. I'm thinking the fork has to be moving to engage the switch otherwise the light would not come on. I guess the next step would be to open it up and inspect it. Are these known for braking internally? can I manually switch it by hand to see it the 4x4 works? Thanks for any help.

 

The switch is just activated by the end of the shaft of the actuator. There is a fork that it is supposed to move, and I suspect it is not.

There is a really good view of how it *should* work here.

I suspect you are going to need to open up the cad, and see what's going on. Careful though, I broke one of the bolts on mine, trying to get them out. That was a pain to extract.