Condition: Some F-150s equipped with a 9.75 Traction-Lok rear axle assembly may exhibit a shudder, chatter and/or vibration during slow, tight turns. This concern may be more noticeable after cold startup and less noticeable once the rear axle fluid warms up.
Vehicles: 2009-’12 F-150 built before March 5, 2012.
Remedy: Install a new vent tube and differential clutch pack. Make sure the vehicle is equipped with the original equipment 9.75 Traction-Lok rear axle assembly before making repairs.
1. Install the axle vent service kit EL3Z-4A058-A. Refer to the instruction sheet included in the parts kit.
2. Install the Traction-Lok rear axle clutch pack replacement kit 9L3Z-4947-D. Refer to the instruction sheet included in the parts kit.
Courtesy of ALLDATA.