I have a 04 SCREW 4x4 with a 4.6 42000 KM. The other day I started hearing a buzzing/chattering (sounds like a ratchet) noise coming from under the truck. I thought it was the brakes at first, but aplication of them didi not stop it. I then switched into 4 HI and the noise was gone, after switching back to 2 HI the sound was gone, but after a few minutes it came back. Seems like something in the transfercase is trying to engage in to 4 wheel. Any ideas as to what could be causing it? Electrical, internal?

Thanks
Greg

 

its not the transfer case. its an IWE trying to engage due to a vacuum leak. the IWE solinoid is the most common culprit.

 

Thanks..that seems to have fixed it.

 

no problem glad i could help

 

Hate to say it, but after about 50 miles it came back. I think I'll pull the hub apart and check the actual IWE. Unless anyone has another idea. Damn dealer charged $119 cad for the solonoid, cant wait to hear the price of the hub.

 

had one today that was interesting, lines had water in them, replaced IWE solinoid and check valves, test drove and same problem, inspected vacuum lines and found line to LF IWE was plugged solid, replaced line and guess what same problem...dissasembled LF and found IWE was seized partly engaged couldnt even move it by pushing on it. replaced the IWE and all was good! just goes to show you how a failure in this system can have a big chain reaction...

 

Thats exactly what it was. I found it by lifting the tires of the ground and using a vacuum pump on each wheel to see if the IWE was dissengaging. The spring inside the IWE was a pulverived pile of rust holding it partialy engaged.

Thanks to all