Hey guys.newbi here with a problem I thought I had correctly diagnosed. Truck would not shift into 4WD high or low. No light in dash etc. After tapping transfer shift case motor few times I was good to go...so I ordered new Dorman replacement motor. Replaced but still have same problem. Did I miss something? I tried gently tapping new motor and voila it worked again..for about 2 minutes...
Thanks in advance for any guidance.

 

either binding inside, or a poor electrical connection.

 

I'm gonna check the wiring but how can I verify if it's binding?

 

Hey guys Newbie here myself, but have been reading these threads for awhile now and your questions made me sign up, hopefully I can help. I was having the same issue with my 06 XL, and after a extremely long frustrating time and almost about to blow $300+ at a dealership, and I hit the forums and found my salvation. Our 04-08 trucks 4x4 is a vacuum system and because of that air leakage is usually the culprit. Also there was a huge design flaw with the solenoid and water damage (which was my problem! cost me $13) here's a link to something similar . You can YouTube how to locate and replace.
Otherwise check the small air hoses from that solenoid to each wheel and look for cracks, breaks, or pinches.
Hopefully this helped.
Good luck

 

the vacuum system is used to engage or disengage the front wheels to the axle ........ The problem with getting the drive shaft to TURN or being in LO or HI is related to the electric motor on the transfer case.... If the transfer case motor does not shift, don't matter what happens on the front axle.


If you have " vacuum problems with the IWE or the solenoids, you should hear GRINDING or noises in the front end.

 

When you put the truck into 4x4 are you pressing on the brake? Truck needs to know the brake is pressed down before it will shift to 4H. Then to go to 4L you need brake pressed and in neutral. That's how my 2004 works.