Ford F-150 Owner's Manual page 205

For 2WD vehicles
E183740
Turn the control to ON.
Once the indicator light
illuminates in the information
display, both rear wheel axle
E163170
shafts will be locked together providing
added traction.
If the indicator does not come on, or the
indicator turns off while driving, one of the
following has occurred:
• The vehicle speed is too high.
• The left and right rear wheel speed
difference is too high during an
engagement attempt.
• The system has malfunctioned and is
accompanied by a message in the
information display. See your
authorized Ford dealer for assistance.
• The vehicle is experiencing an anti-lock
brake activation.
F-150 (TFC) Canada/United States of America, enUSA, Edition date: 201607, Second Printing
Rear Axle
202