Two problems related to differential unit have been reported for the 2006 Ford Mustang. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2006 Ford Mustang based on all problems reported for the 2006 Mustang.
Driving on interstate the car lost power momentarily and then resumed normal driving. Within a few miles the vehicle began making a loud noise which sounded like a flat tire. Upon beginning to move to side of road, tapped brakes and vehicle began rocking, shaking and screaming with metal on metal noise. Vehicle was rocking front to back and fishtailing side to side. Vehicle lost all power steering and had no brakes. Upon disengaging brake, vehicle continued to make metal on metal noise, but was coasting with little steering. I was able to maneuver the vehicle onto an exit ramp, but upon nearing the end of the ramp I had to tap brakes again causing car to skid sideways, lock up and violently come to a stop. Upon exiting the vehicle I saw a large part of the car on the ground, glowing orange. This proved to be the drive shaft. I was told that the rear differential disintegrated causing the failure. The rear end, rear driver spring, drive shaft and other components were replaced. This was such a violent incident it caused the clamp which holds the drive shaft in place to be ripped from the frame of the vehicle which caused a hole, which needed to be welded, to occur. Old parts were confiscated to be returned to Ford for review.
Squealing/grinding noise from rear end on low speed turns at 7000 miles. Dealer identified the source as the rear axle and put in a new diff clutch pack. Vehicle was fine for a few months but the same sound has returned, however it is intermittent and quieter. Mileage is now about 14,000. Rear ends should not be wearing out every 10k miles on a high performance vehicle.