Back in August, the National Highway Traffic Safety Administration opened an investigation regarding the Getrag MT82 6-speed manual transmissions found in 2011+ Ford Mustangs.
At the time, Ford was already carefully monitoring customer feedback as well as online forums as well to better understand the issues concerning the transmission.
While only 3 percent of all transmissions were effected, Ford has found that most of the issues were related to cold shifting, a clutch plate bolt defect, clutch stay out, and 5th gear synchronization. Ford assures that none of the issues found will cause a safety risk.
Of the issues reported, 44 percent were related to higher than expected shift efforts in cold ambient temperatures when the car first starts. Initially, the MT-82 transmission was given a thicker, higher viscosity transmission fluid to address gear noise. However, customers are allowed to request a lower viscosity fluid to minimize shift efforts.
Next a clutch plate bolt issue reportedly caused gear selection to become more challenging over time. Complaints indicated notchiness and grinding noises as a primary concern. Ford found that this attributed to clutch fasteners that got loose over the duration of the vehicle's operation. A revised fastener was designed and put to production in October 19, 2010 to fix the issue and a special service message number was issued to aid technicians in identifying this concern.
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Ford Releases Findings on NHTSA Mustang Transmission Investigation on Autoguide.com