I'm currently 600 miles from where I need to be on Thursday. The military doesn't like when you don't return from leave so this is a pressing matter.

Here's what's happening. My transfer case is engaging into 4hi on its own. It happened on the drive down here a couple times. Keeping it below 60 or so seemed to help. I took it to the Ford dealer to get fixed. They said it was caused by a leaking windshield corroding the gem and fuse box. They replaced those and said it was good. Didn't have an issue for about a week and then it happened again, but worse. In and out of 4hi every other second this time.

What else could be causing this issue? I picked up a replacement shift motor and solenoid. Should I try to replace those in the morning? As of now, I'm planning on removing the front driveshaft and driving back in 4hi.

I hate taking things to the shop for this exact reason. They didn't fix the problem. Dealer up there will be hearing from me. If I have my way, they will actually fix the problem and charge the dealer down here.

 

Doesn't show signature on mobile page. Don't remember if I have one or not. Truck is a 2002 f350 7.3 4x4 (obviously)

 

I would just unplug the motor so you can drive back.

 

It happens when motor is unplugged too

 

I would just remove the front driveshaft and get to your duty station. They don't take it too kindly to not sign in from leave on time! Where you headed to brother?(Ft Lewis for me).

 

Sounds like you have ESOF. I would just disconnect the vacuum lines to the hubs, cap them, and tie them up. It won't stop the T-case from shifting into 4WD, but you won't be connected at the wheels so you won't hurt anything.

 

I'm currently in Orlando. Heading back to camp lejeune, nc.

I have warn hubs so I know they aren't engaging. When it goes into 4hi, the transfer case makes horrid grinding noises and clunks into range. I know it can't be good fit it. Worse case scenario, I'll take driveshaft out and drive back slow.

 

Why take the drive shaft out? If your hubs aren't engaged shift it to 4-hi and roll out. No reason to go slow or remove the drive shaft.

 

I don't see anything wrong with driving in 4H. I would check to make sure you got differential fluid , mine was 1 qt low when I checked it.

if the hubs are unlocked, agree on why remove shaft question.

 

Quick update: Slowly but surely, I got the truck home. Didn't have much time to work on it since, but I did get the shift motor replaced. No improvement. I still have a grinding over 60mph. I'm thinking it is time for a full transfer case rebuild. Not sure what would break in order to cause it to engage on its own, but I figure if I'm going to tear it down, I might as well rebuild it and try to eliminate potential problems as I go. I cannot afford a new transfer case right now, so as I have funds available, I will start investigating/eliminating smaller things until I find the culprit.

 

Nick, I would pick one up at a bone yard, they are cheap and plentiful, cause normally they never go bad. Except the motors which your going to replace anyway. That's why I have a lever to pull when I need 4WD.

 

The wiring harness on my 99 with esof will not latch fully , I at times have to get under the truck to press it on again to engage the 4x4.
At times I have had the indicator light come on and have to pull over and wiggle the harness and 're seat it , to get the light off.
If I have been in 4 low and the light goes off , the truck is stuck in low range.
My point is it might be in the connector for the shift motor , loose pin or harness connector.