Got a mystery for you ...

Changed the vacuum actuator switch on my transfer case... Now it won't go into 4hi. It'll go into 4lo and 2hi

When I hit 4hi you hear it try to switch over but the 4hi and 4lo buttons just flash before it goes back into 2hi

Any ideas ?

 

Sure you didnt switch vacuum lines around? I would take a look at the vacuum actuator also. You can also check the engagement cable by hand by squeezing the actuator and make sure its sliding and not seized.