When i put my 2010 f350 in 4x4 it works as it should and the 4x4 light comes on however when moving or while stoped it is no longer in 4x4 but 4x4 light is still on. I have to turn it off and back on to get back in 4x4. It did this about a dozen times in a hour today. Could this be the solonoid on the transfer case or?

 

You are positive that the 4wd is disengaged (vs maybe the light just going out)?

 

Light stays on, definitely kicks out of 4x4. Happens while moving or stopped

 

Is it the transfer case that is disengaging...or are the hubs coming unlocked? I'm assuming ESOF ? Try turning the hubs from auto to locked and see if that makes a difference.

 

Not sure, guess i need to see if the shaft turns next time it happens, or lock the hubs and if it happens then i guess transfer case is disengaging. So if i lock hubs and it comes out its probably solonoid on transfer case? If its fine with hubs locked manually its a vacuum issue at hubs? Do i have that right?

 

Yes correct.... Auto lock does use vacuum...but it's not constant vacuum. They use vacuum pulse to lock...and then are held in the locked position by metal tabs. I have heard rumors that these metal tabs can be defective and cause hubs to unlock. So with hubs turned to lock....this should pinpoint a shift solenoid issue or a hub issue.

 

I’m no mechanic, but I’ve never seen anyone have a problem with the transfer case disengageing by itself once it’s engaged.

It shouldn’t have anything to do with the hubs.

I’d think that it has something to do with the wiring into the transfer case. Maybe it’s loose or chaffed and somehow shorting?

try putting it into 4lo (need to be in neutral with foot on the brake) and see if it stays engaged. If it does, put it ito 4hi and see if it stays engaged there niw.

 

Thanks for the info

 

I think this is all in your auto hubs. I just went through that with a vacuum leak in one of my hubs. I had intermittent 4x4. It always worked as soon as I engaged the switch but would kick in and out as it tried to maintain vacuum to keep the hubs in. The big main seal in behind the hub will cause this as well if its starting to leak.

 

Did your 4x4 light stay on? Ive never noticed mine kick back in, just goes out unless i turn it off and back on again.