The National Highway Traffic Safety Administration has closed its investigation into 29,807 2011-2012 standard transmission Ford Mustangs. The probe looked into complaints of shifting issues. The federal safety regulators concluded that a recall was not in order.
Complaints of rough shifting
According to the NHTSA, the investigation began in August in response to 364 separate complaints of faulty or rough shifting in new Mustangs.
Inside Line reports that Ford conducted its own investigation. That probe identified several possible ways that shifting troubles could have occurred. Those included cold transmission fluid, clutch stay-out at high engine speeds, gear grinding and clutch plate bolts loosening over time.
Automaker blames drivers
Ford told the federal safety regulators that the issue has caused no accidents. The Dearborn automaker chalked the problems up to the driver’s own “shifting behavior,” saying the complaints stemmed from the customer’s “unfamiliarity with the performance-style shifter.”
The automaker went on to say that much of the complaints could have been solved by letting the engine run for five minutes, allowing the transmission fluid to warm up, before driving. Once the Mustangs warmed up on the road, the issues disappeared.
Ford admitted to cold-start issues with the the car’s Chinese-built Getrag MT82 six-speed engine. The automaker issued a bulletin to service technicians recommending a lower viscosity transmission fluid to improve the cold shift issue.
The NHTSA found that only five of the complaints had to do with loosening clutch plate bolts. And none of those incidents prevented the vehicle from starting or shifting. Ford says it has overhauled the bolts to eliminate the problem and has issued a service tech bulletin.
The NHTSA said in its final report:
“There is no indication of loss of motive power or unreasonable safety risk associated with the alleged defect in the subject vehicles. This preliminary evaluation is closed.”