2008 5.4L triton. When I'm in the snow or mud and engage the 4 wheel drive I hit the gas and I can hear what I think it is the hub spinning but it will not turn the wheel what do you guys think that is. hoping it is not my transfer case

 

MY 06 is doing the same thing , I am replacing the wheel hub and actuator but first check your vacuum .

 

Yea checking vacuum would be first. When mine started randomly engaging it was the (not sure of name) valve that controls the lines. Sometimes it would engage sometimes not. Sometimes partially engage at highway speeds. On my 07 5.4 it was right on the firewall behind the battery. Very easy change can't remember the cost for the part though.

 

You also might want to read the second thread of this forum "All You Want to Know About the IWE System" a lot of good info in there.







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