Note:  The electronic locking differential (ELD) is for off-road use only and is not for use on dry pavement. Using the electronic locking differential on dry pavement can result in increased tire wear, noise and vibration.
The electronic locking differential is a device housed in the rear axle that allows both rear wheels to turn at the same speed. The electronic locking differential provides additional traction should your vehicle become stuck. You can activate the differential electronically and shift it on the fly within the operating speed range. The electronic differential disengages when the vehicle speed exceeds a set value and it re-engages when the vehicle speed goes below a set value. Refer to the following table for the speeds when the electronic locking differential turns on and off. It also engages based on certain selected drive modes.  See  Principle of Operation.  The electronic locking differential is for use in mud, rocks, sand or any off-road condition where you need maximum traction. It is not for use on dry pavement.
Note:  The electronic locking differential is not available in 2H.
Electronic Locking Differential Engagement Speed and Availability

Terrain Modes (4WD Modes)   Maximum Engagement Speed   Automatic Disengage Speed   Automatic Re-Engagement Speed  
Normal (4A, 4H)   20 mph (30 km/h)25 mph (41 km/h)20 mph (30 km/h)
Sport (4A, 4H)   20 mph (30 km/h)25 mph (41 km/h)20 mph (30 km/h)
Weather (4A, 4H)   20 mph (30 km/h)25 mph (41 km/h)20 mph (30 km/h)
Mud/Sand (4H) 1   No set speed   No set speed   No set speed  
Baja (4H)  
Rock crawl (4L)1  
4WD Mode   Maximum Engagement Speed   Automatic Disengage Speed   Automatic Re-Engagement Speed  
4L   55 mph (90 km/h)62 mph (100 km/h)55 mph (90 km/h)

1Automatically engages when these drive modes are selected. You can manually override the automatic engagement by pressing the electronic locking differential switch.
Note:  The selection of 4L overrides the Terrain Mode based speed engagement and disengagement.
Note:  The Advance Trac system has the ability to take over control of the electronic locking differential and disable it during driving maneuvers when necessary.
When you switch the system on, if you do not meet the required conditions for electronic locking differential activation, the instrument cluster displays the appropriate information guiding you through the proper activation process.
Activating the Electronic Locking Differential
Note:  Do not use the electronic locking differential on dry, hard surfaced roads. Doing so can produce excessive noise, vibration and increase tire wear.
Note:  If the electronic locking differential has difficulty disengaging, release the accelerator pedal and turn the steering wheel in the opposite direction when rolling.
Missing Image
Push the center of the 4WD select knob to manually activate and de-activate the electronic locking differential. An LED on the knob illuminates to indicate the system is activated.
Note:  The LED may illuminate automatically based on terrain mode selection.
Missing Image  Once the indicator light illuminates in the information display, both rear wheels are locked together providing added traction.
If the indicator does not come on, or the indicator turns off when driving, one of the following has occurred:
  • The vehicle speed is too high.
  • The vehicle is experiencing an anti-lock brake activation.
  • The left and right rear wheel speed difference is too high during an engagement attempt.
  • The system has malfunctioned and is accompanied by CHECK LOCKING DIFFERENTIAL in the information display. See your authorized Ford dealer for assistance.
Operating ELD With a Spare or Mismatched Tires
On vehicles with an ELD, the size of the spare tire can affect performance of the system. If there is a significant difference between the two rear tires, you may have limited ELD functionality. If the electronic locking differential has difficulty disengaging, release the accelerator pedal and turn the steering wheel in the opposite direction when rolling. We recommended engaging and disengaging the ELD at a stop when you have the spare mounted on the rear axle.