After putting it in 4 wheel, when I press the 2 wheel button, I hear a click in the dash, the light flashes but it still stays on 4 wheel high.

I checked the vacuum hose on the driver fender and all is hooked up. We have replaced 4 wheel drive actuator that sits on top of the transmission which has the ball bearing inside which was stuck. Not sure if that's what its called, also at the time we checked the 4 wheel something that sits under the battery, it was working like it should but didn't check it tonight.

No SES lights are showing either.

I drove it on gravel about 3-5mph and pressed the 2 high button, went in reverse and no luck.

Any other ideas?

 

Also, it wont go in 4 wheel low, the light flashes for several seconds and that's it.

 

Just unhooked the battery for 30 mins, still same result.

 

Just removed the battery and took a look at the vacuum motor and I'm able to pull it and it moves, the device seems to be in 2 wheel drive state as it is not pushed in.

I then removed the 4 wheel drive fuse, the lights go off on the push buttons and then the fuel gauge doesn't work.

 

Any ideas? I've been driving in 4 wheel drive all week

 

ive got same problem did you ever get it fixed?

 

Nope

 

Plug the vacuum hose to the actuator under the battery to disable the 4wd. Is the cable on the front axle stuck? Mine was on my blazer last winter after driving thru some deep water then it was freezing out. Replaced the cable and about 4oz of water came out my diff. My 4wd worked like a champ after I replaced the cable.

 

could always remove the encoder motor and see if the peg is in 4x4 position, it will just turn back to 2wd with a wrench. or start truck, remove battery and pull vacuum line off actuator see if its getting vacuum

 

Haven't tried any of that yet but with the drive shaft removed, the push button still shows up as 4 wheel drive. When you press the button it clicks in the passenger dash area and thats it.