Back in August we reported that the National Highway Traffic - TopicsExpress



          

Back in August we reported that the National Highway Traffic Safety Administration was opening an investigation into the 2011+ Mustang’s Getrag MT82 6-speed manual transmission. Since the car’s introduction with the new transmission, owners have reported a variety of issues including binding gears, difficulty engaging in shifts and excessive noise and vibration. At the time Ford stated that they would “fully cooperate with the government as they review this matter.” Now Ford has issued an official response to the NHTSA investigation with a report detailing their investigation into the Mustang’s transmission problems, the problems discovered, and the actions taken to rectify the issues. While the report is quite extensive, we’ve broken down the basics of for you. The basics of Ford’s response to NHTSA investigation of the Mustang’s MT82 transmission: Ford was aware of the problems via direct communication from customers and monitoring of online forums Approximately three percent of transmissions were affected Ford investigated a variety of issues and found issues with cold shifting, the clutch plate bolt, clutch stayout, and 5th gear synchronization (detailed below) Each of the problems was addressed (detailed below) Many other factors resulted in the reporting of problems, including driver effect, the skip-shift feature, the influence of online forums, vehicle modifications and abuse. None of the issues caused a safety risk Ford has no plans for modifications related to the Mustang or the MT-82 6-speed manual transmission in the next 120 days Introduction Summary Concurrent with the launch of these new powertrains, Ford undertook aggressive monitoring of customer feedback, not only being sent directly to Ford, but also through customer comments in a wide variety of forums such as social media and various Mustang enthusiast forums. Through these varied sources of information, Ford became aware of a range of customer observations pertaining to the new 6-speed transmission. These ranged from reports that the gear shift was “stiff”, that shift efforts were higher than expected when changing gears, to reports of “grinding or notchiness” while completing a gear shift. Although reports associated with shift quality concerns appear to affect a low percentage (approximately three percent) of the vehicles equipped with the MT82 transmission, Ford nevertheless undertook steps to understand the causes of these concerns and to implement improvement actions where appropriate. Ford introduced new engines and transmissions for the 2011 model year to continue meeting higher ustomer expectations for vehicle performance while improving fuel economy. While some customers have expressed satisfaction concerns related to shift quality in these vehicles, analysis of the reports included in the response and a thorough understanding of the design and manufacture of these transmissions and shift controls show that the conditions observed by those customers does not result in an inability to shift into gear or in loss of motive power while driving, and, accordingly, there is no risk to safety associated with the manual transmissions in these vehicles. Summary of Problems and Solutions from Ford Cold Shifting Problems: Approximately 44 percent of the reports indicated higher than expected shift efforts in “cold” ambient temperatures when the vehicle is first started. The MT-82 6-speed transmission was launched with thicker (higher viscosity) transmission fluid than was used previously to address a gear noise issue identified during development. Ford determined that the customer complaints of increased shift effort may have resulted from this higher viscosity fluid and ambient temperatures at or below 60 degrees F. Solution: While these initial “cold” shift efforts may be higher than the driver may have previously experienced, analysis found that the vehicles can be shifted into any desired gear without excessive effort. Nevertheless, Ford worked directly with dealers and customers in an effort to resolve individual concerns and manage the trade-off between the shift efforts and potential noise concerns. Ford subsequently issued TSB 11-3-18 informing technicians to use a lower viscosity fluid, which has appeared to have alleviated the concerns of customers who are not satisfied with “cold” shift efforts. Clutch Plate Bolt Problems: A number of reports identified by Ford alleged increasing difficulty selecting gears over time, along with clutch noise and clutch performance degradation. Investigation of these reports identified grinding or “notchy” gears that were found to be caused by clutch fasteners that had worked loose during vehicle operation. An investigation into the root of the cause identified an issue with the fastener/joint design at the clutch to flywheel interface that was exacerbated by the higher transmission input speeds provided by the new engines. Solution: A revised fastener was designed and put into production October 19, 2010. The revised fastener was concurrently made available for service and a special service message (21614) was issued to aid technicians in identifying the concern. Clutch Stayout Problems: Approximately 24 percent of the reports refer to an issue identified by Ford as “clutch stayout” where the rotating inertia of the clutch components can be higher than the spring force provided by the clutch pedal return spring when gears are shifted at engine speeds greater than approximately 4,000 rpm. Under these conditions the clutch will reengage when engine rpm is reduced to a speed where the clutch pedal return spring overcomes the rotating inertia of the clutch components. This condition does not prevent selection of any gear. Solution: An investigation into the root cause of these reports identified that variability in the spring forces in the population of clutch pedal return springs allowed some springs to be below the expected force values and allow the condition to occur. Replacement clutch pedal parts were made available and a revised spring design has been implemented. 5th Gear Problems: Some of the customer feedback received by Ford alleged “grinding into gear” or “notchiness” during shifting not caused by the previous problems. Ford investigations identified some component quality issues relating to the synchronizers for fifth gear. Solution: Corrective action was taken Other Possible Causes of Shifting Problems Driver Effect: Some vehicle evaluations by dealer service managers or field service engineers found that the driver’s shift quality concerns were caused by their own shifting behavior. The 6-speed design differs from its 5-speed predecessor in that it has a narrower gate – the distance to engage the 3-4 or 5-6 gates from the 1-2 gate is narrower than on the 5-speed transmission. Ford believes that many driver reports of shift quality issues may, in fact, pertain to the narrower shift gates and relocated reverse gear position of the new 6-speed transmission. Skip-Shift: To further improve fuel economy, Ford incorporated “skip-shift” technology into the new 6-speed transmission. A thorough review of the reports identified found that one percent mention the skip-shift feature. A common expression in these reports is that the operator did not notice the shift to second gear had been gated to fourth. However, the skip-shift feature is only active under certain circumstances and does not result in an inability to shift. Allegations that the skip-shift feature either causes missed shifts or causes the vehicle to slow and become a risk to safety are not supported by the parameters necessary for skip-shift to be activated. Influence of Online Forums: Base on the review of comments in social media resources, it is reasonable to conclude that online forums can significantly influence the numbers and nature of concerns reported to both Ford and the agency. In particular, participants in one blog not only advocated contacting either Ford or the agency to gain attention to the matter, but also suggested the type of information that should be included in their contacts. One forum observed by Ford included guidance to make sure to explain how their concern was a “safety issue”. Vehicle Modifications, Abuse: Ford expects that owners may make some modifications to their vehicles for a variety of reasons. Inspections of some complaint vehicles have found modifications that may negatively affect shift quality and clutch and transmission durability. In addition to improper vehicle modifications, inspection of complaint vehicles often finds evidence that a vehicle has been abused. As a consequence, some owners may be disappointed that the warranty coverage was denied, and some of the complaints received by Ford and the agency may result from the associated dissatisfaction. Conclusion Summary While there have been some customer satisfaction concerns with the MT82 6-speed transmission in the subject vehicles, none of the underlying causes result in an inability to shift into gear or loss of motive power. The issues identified by customers have related to higher than expected shift efforts on a “cold” transmission, clutch stayout at higher engine rpms, gear clash or grinding, the skip-shift feature, and backing out of the clutch plate bolts in some early production vehicles. While the latter condition potentially could result in an inability to shift into gear, it is a very rare occurrence and can only inhibit the ability to shift into gear after prolonged and obvious indication to a driver through vibration, increased shift efforts or gear clash or grinding. As a result of Ford’s monitoring of these customer concerns, observations by dealer service personnel and Ford field service personnel, and vehicle inspections, we have concluded that the reports generally relate to custom unfamiliarity with the performance style shifter with its narrow gates, the skip-shift feature, vehicle modifications and vehicle abuse. Diligent monitoring of many customer feedback sources caused Ford to immediately evaluate and address several of the customer concerns. Some customer vehicles have experienced more than one repair attempt to address a particular issue and, regretfully, some customers have not had the level of satisfaction that Ford desires. Ford is committed to continually monitoring its products to provide the highest level of customer satisfaction possible. That is the case with the MT82 manual transmission. A review of the reports provided in response to this inquiry has found that the reports have continued to decline as each action was put into place by Ford. The 2012 model year field data, although immature, indicates the actions taken have been very effective. In summary, all the actions to date have been implemented to address sources of customer dissatisfaction related to “shift quality” concerns. The concerns described in the reports to Ford do not result in an inability to shift into gear or loss of motive power and clearly do not present an unreasonable safety risk. This observation is supported by the fact that there are no reports of any highway accidents or injuries related to this concern, even with the broadest definition of the alleged defect utilized to search for reports.
Posted on: Sun, 21 Jul 2013 11:28:26 +0000

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