Im very confused with my 4wd. I have a 1998 blazer with pushbutton 4x4. Everything seems to work, The 4hi and 4 low lights come on, and it sounds like the transfer case switches, no service 4x4 light. Yet it doesnt seem like the front axel is driving. I parked the truck on a sheet of ice, put it in 4 hi, and gassed it, but the front wheels dont spin, while the rear wheels just burnout. Any thoughts?

 

i dont have a 4wd ,but is the driveshaft def hooked up to the truck .. have someone lay on the ground near the truck dont run them over have them look to see if the shaft is turning when you start to roll or put the truck up on jackstands and see what happens..maybe sumthing let go in your transfer case..I`m only giving thoughts since i dont own a 4wd but just tryin to give 2 cents

 

*Moving to 2nd Gen Tech*

Sounds like the classic front axle vacuum actuator problem. This can be caused by a number of things. Faulty vacuum switch on the transfer case, broken vacuum line between the TC and the actuator, faulty actuator, or a seized actuator cable rounds out the problem areas. The vacuum actuator is located under the battery. So you'll need to verify that when the 4wd is engaged, that you have vacuum to the actuator.

 

this is the same thing happening with mine

 

I think you may need the accuator that engages the trasfer case

 

I have the same problem! I followed my vacuum line from my actuator only to find it its broke in half and I cant find out what It hooks up to. Can somebody please help me.