Automotive News reports that a lawsuit filed in California last year goes after Ford for alleged defects in the six-speed manual transmission found in 2011MY to 2019MY Mustangs. Starting with the 2011 model year, the Mustang switched to a Getrag MT82 gearbox that replaced the Tremec T5 gearbox in V6-powered Mustangs and the TR-3650 in the Mustang GT. In its first year on the market, owners lodged 364 unique complaints with the National Highway Traffic Safety Administration (NHTSA) out of a total of 444 complaints, citing issues such as "increasing difficulty selecting gears along with gear clash or grinding." The NHTSA conducted a four-month investigation, closing the matter toward the end of 2011 with the finding, "There is no indication of loss of motive power or unreasonable safety risk associated with the alleged defect in the subject vehicles." The agency's assessment didn't say the gearbox wasn't flawed, only that it wasn't unsafe.
The court documents claim the core issue is that the MT82 was designed for smaller cars "with much lower horsepower" than the Mustang, and Ford and Getrag failed to re-engineer the sufficiently robust internals for the Mustang even as the gearbox included features intended to increase smoothness. Various places online question if the MT82 was born of cost-cutting, after Ford and Getrag entered a joint venture in 2001 and used their plant in Nanching, China, to assemble the six-speeder supposedly on better financial terms than the Mexico-built Tremecs.
The lawsuit charges that "The transmission is defective in its design, manufacturing, and or materials in that, among other problems, the transmission slips, jerks, clashes gears, and harshly engages; has premature internal wear, increased shift efforts, inability to drive, and eventually suffers a catastrophic failure," and, "Ford repeatedly failed to disclose and actively concealed the defect from class members and the public and continues to market the class vehicles without disclosing the transmission defect."
According to the suit, which seeks class-action status, owners say Ford sent seven Technical Service Bulletins and special service messages over the years to deal with the matter. Directions to service departments included measures like replacing the third/fourth shift forks, third/fourth gear synchronizer hubs and sleeves, countershaft third gears, the shift lever, clutch pedal position switches and the brackets, and draining and refilling the gearbox. For the 2018 model year, Ford replaced the MT82 with the MT82-D4 that had been upgraded with parts like stouter synchros, a twin-disc clutch, and a dual-mass flywheel. The Mustang owners involved in the court action say the attempted repairs haven't cured the issues, and the MT82-D4 suffers from the same flaws.
Unless the problems are addressed properly, owners believe the ultimate result will be an "inability to drive, and eventually ... a catastrophic failure."
The Mustang suit, seeking $5 million in damages, has been moved to the U.S. District Court for the Eastern District of Michigan. Ford said before that it believes the problems noted in the lawsuit are the result of simple wear and tear. Beyond that, the automaker refused to comment on the litigation.