Truck stuck in four wheel drive

1999 FORD EXPEDITION
240,000 MILES • 5.4L • V8 • 4WD • AUTOMATIC
Avatar
JAYAR BELISLE
  • MEMBER
  • 6 POSTS
When in drive/reverse out of a parking spot or make a turn truck makes a humming, clunking, and slows down or stops and have to give it more gas to move. When i drive straight all it does is hum. When i turn the electronic 4x4 knob the 4x4 light turns on and i hear relay clicking.
Apr 6, 2019 at 12:34 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.
Advertisement
Avatar
STRAILER
  • CAR REPAIR CONTRIBUTOR
  • 54,189 POSTS
It sounds like the encoder motor is seized up not tracking correctly. Here is a diagrams so you can remove the motor to see if it is working correctly. Please check it out and get back to me.

Check out the diagrams (below). Please let us know what happens.

Check out the diagrams (below). Please let us know what you find. We are interested to see what it is.
Images (Click to enlarge)
Attached Media
Attached Media
Attached Media
Apr 8, 2019 at 1:13 PM
Advertisement
Avatar
JAYAR BELISLE
  • MEMBER
  • 6 POSTS
I removed the shift motor and the transfer case was already on 2 hi and the video is the shift motor switching AWD to 4 HI to 4 LO back to 4 HI to AWD.
Video (Click to enlarge)
Attached Media
Apr 9, 2019 at 3:56 AM
Avatar
STRAILER
  • CAR REPAIR CONTRIBUTOR
  • 54,189 POSTS
Thanks for the video, yes that seems to be working fine, can you tell where the noise is coming from?
Apr 9, 2019 at 11:39 AM
Avatar
JAYAR BELISLE
  • MEMBER
  • 6 POSTS
The noise is coming from the front of the truck.
Apr 11, 2019 at 6:12 PM
Avatar
STRAILER
  • CAR REPAIR CONTRIBUTOR
  • 54,189 POSTS
Can you go for a ride and take a video so I can see what is going on?
Apr 12, 2019 at 10:10 AM