Okay this is on my 1997 Chevy Blazer 4.3 Auto 4wd.

To start my fourwheel drive stopped working. So I checked all my vacum lines and checked them twice! I then replaced my diaphragm (actuator) under the battery. I also replaced the switch on the transfercase. And my fourwheel drive is not working

This is what happens,
I got to put it in 4Hi driving under 25mph and it lights up as if going into 4Hi, however it is remaining in 2wd. At stop it does the same thing for 4hi. Then for 4lo in neutral put it in 4lo the 4lo light lights up and stays lit as if its in 4lo, then drive, it feels real torquey, however it is still in 2wd. The front isnt engaging!

So I am lost at this point as to what else it could be. Any suggestions or tips what to look at or replace? I am supposed to get 6-8" of snow in the next day so I need my 4wd back! Thanks guys!

 

Anyone??

 

Search is your friend. There are MANY threads concerning the front axle not engaging. No need to wait for someone to respond when you can read all about it.

Have you verified that you are getting engine vacuum to the actuator when you are in 4wd? Does the cable move freely and at least a 1/2"?