Limited Slip Axle may Vibrate, Bind, or Judder in low speed turns on Ford F-150

New TSB may be available

According to Ford Bulletin 06-04-04

Some 2003 + INDEPENDENT REAR SUSPENSION (IRS) AXLE F-150 vehicles equipped with a 9.75″ or 8.8″ limited and Mustang vehicles equipped with limited slip rear axle, may exhibit a chatter, shudder, a binding sensation, or a vibration during low speed turns. On 4X4 vehicles, the sensation may appear to be originating from the front axle or the steering gear.

First verify the condition. On 4X4 trucks ensure that Modifier (XL-3) for fifteen (15) minutes prior to the vehicle is in 2WD, to isolate the rear axle. If the condition is verified to be in the rear axle, replace the limited slip clutch pack.