Why Won't My 4-Wheel Drive Engage?

[Reverie]

I have an '03 Eddie Bauer, 6.0 4x4. I noticed the other day that the 4x4 no longer engages. I can select 4 High or 4 Low and the indicater illuminates in orange but nothing happens. Any thoughts?

Reverie

[thatguy2010]

check the wiring plugs on the transfer case. this happened to me and I had to go through and tighten all the connections.

[Articcatzl440]

could be your vacuum pump

[Reverie]

It was suggested I change the vent settings on my climate control and they work fine. Should I take this to mean the pump and the Vacuum Solenoid work right?

Reverie

[NotStock]

Is your front driveshaft engaging? If it is spinning however the front wheels are not, you need to check your vacuum lines. The lines that run from your knuckles up to the frame are prone to cracking and failure. You can manually lock the hubs aswell (if your truck even has auto hubs).

[ClaytonG]

i recently had this problem. My 4x4 would not engage and my electronic climate controls would only blow out of the defrost. Turned out to be the vacuum pump, about $100 from napa.

[forddieseldoctor]

If your 4x4 indicator lights are working properly then your transfer case motor is shifting properly. Your issue is more than likely in the front hub area. You need to see if you have vacuum to the front hubs when you shift it in to 4x4. It uses the vacuum to engage the hubs. If you have vacuum when both lines are plugged off then you more than likely have an issue with the front hub vacuum seals.