In the automotive world, change is a constant, and if you’re not keeping up, you’re falling behind. New technologies and methodologies are key to gaining an edge in the market, and companies invest billions each year trying to find the next big thing, or even the next minor incremental improvement.
In just such a quest, Ford Motor Company decided to explore an alternative to the traditional automatic gearbox, aiming for greater fuel efficiency in their small cars. On paper, there were gains to be had. Unfortunately, not everything went according to plan.
The traditional torque-converter based automatic gearbox was a game-changer for the automotive world. With the advent of the self-shifting transmission, drivers had one less complex skill to learn, and cars became much less taxing to drive, particularly in high-traffic, slow-speed environments. However, the fluidic coupling of an automatic transmission isn’t as efficient as simple meshing gears, a tradeoff that harms fuel efficiency. To get around this, Ford instead decided to create a dual-clutch automated manual transmission for its small cars.
Dual-clutch transmissions use a pair of clutches, one for odd-numbered gears, and another for even numbered gears. As the car accelerates in one gear, the transmission can preselect the next gear, and then engage the opposite clutch while slowly disengaging the other. This allows for nearly-instantaneous shifting while maintaining torque output to the driven wheels for the duration of the shift. Finding their first road application in high-performance supercars in the 90s, the technology has slowly trickled down to cheaper vehicles over time. Most dual-clutches, particularly those for high-torque applications, use a wet clutch system, where the clutch plates are bathed in oil. Ford wished to maximise fuel efficiency, and instead chose to go with a dry clutch system. The dry clutch eliminates pumping losses from the oil in the transmission.
What in the world are you thinking going with a dry clutch?
With an eye firmly fixed on improving fuel economy numbers, the Powershift transmission was pushed through development, to be installed on the 2011 Fiesta and 2012 Focus models. In the lead up to production, problems were already apparent to Ford engineers, who were struggling to calibrate the transmission’s computer controls to allow the vehicles to drive smoothly and safely.
Early pre-production testers had issues with launches from a stop and shift quality. Often, vehicles would lurch violently when taking off from traffic lights, or shudder under power. Efforts were made to solve the problems in software, with tricks used to modulate the clutch engagement to try and better control the torque delivery. Unfortunately, none of the fixes stuck. The dry clutch system faced fundamental problems, with the inconsistent friction coefficient making it difficult to program the transmission controller in a way that could keep things running smoothly.
In a parallel to another automotive engineering disaster, the Takata airbag fiasco, Ford were well aware of the issues with the transmission prior to launch. In one document presented to court, a product development engineer emailed colleagues outlining issues with the transmission’s performance. Launches were a particular issue, with the email being sent just six months prior to launch of the first Focus models to feature the transmission.
Despite this, the company pressed on, and millions of vehicles were sold with the Powershift transmission fitted. In a short period, complaints began to flood into the NHTSA. Particularly of concern was the tendency to suddenly shift into neutral when there was a loss of communication or other fault with transmission components. This behaviour was not considered as inherently dangerous by Ford, as the driver would still have full control over steering and braking systems.
In the face of this complacency, incidents continued to stack up. Cars returned to dealerships time and again for repair, with no proper fix available. Crashes began to implicate the Powershift transmission. Drivers reported cars lurching forward in parking lots into stationary objects, to being rear-ended due to a sudden loss of drive on the highway. Several fatal accidents have been attributed to the transmission by victim’s families. However, due to the complex nature of the incidents involving a loss of control, proving this as a definitive cause has been difficult. Ford have declined to accept the allegations in these cases.
With millions of vehicles fitted with the Powershift transmission, the inevitable result was a series of lawsuits against Ford. Class actions were undertaken in the United States, Australia, and Canada. In many cases, Ford initially declined to offer refunds or replacement vehicles at no cost, leading to a backlash from regulators. Eventually, Ford elected to settle in most cases, with warranties extended for Fiesta and Focus models fitted with the affected transmissions.
The fallout was a massive reputational hit to Ford, with following models of the Fiesta and Focus returning to a standard torque-converter based automatic transmission. The high cost of repeated transmission repairs also weighed on Ford in warranty costs, estimated to be to the tune of $700 million.
One wonders whether the cost of a late-stage switch back to a more traditional automatic gearbox would have been cheaper in the long run. In addition to causing less inconvenience and heartache to customers, the lower warranty costs and improved reputational standing are worth considering. It’s likely that Ford has had a stern, hard look at internal policies in the years since to determine just why such a defective transmission was allowed through to production. As always, it pays to get your quality assurance out of the way early, before sending millions of defects down the production line and out into the world.
Source : https://hackaday.com/2020/06/03/fords-powershift-debacle/1574