New Ford 6 speed automatic bumps Escape mileage 4-6 percent

When Ford launched the redesigned Escape and Mariner compact CUVs last year, the bodies and interiors were all new but the powertrains were largely carried over from the first-generation models. For the 2009 model year, that issue has been addressed with thorough upgrades to both four- and six-cylinder engines. We'll talk more about the engine upgrades next week after we drive them. In the meantime we got an early look at the new automatic transmission for the non-hybrid models. The previous four-speed unit is replaced with an all-new six speed unit dubbed the 6F35.

The new transmission is built at Ford's Van Dyke transmission plant in Sterling Heights, MI in addition to the 6F50 that debuted in the Taurus, Edge and other Ford, Mercury and Lincoln vehicles last year. The new unit uses three planetary gear-sets and five clutch packs to provide the six gear ratios. The extra two ratios allow for a wider overall spread compared to the older four speed. Continue reading about the 6F35 after the jump.

The top gear has the same ratio as the old transmission but first gear is lower. Combined with a numerically lower final drive ratio, off the line acceleration capability is retained while the engine speed while cruising is reduced. The increased number of ratios also allow for smaller steps between gears so that the engine doesn't have to rev as high in each gear. This helps to reduce both noise and fuel consumption. Combined with various internal design improvements, the new transmission helps achieve a 4-6 percent improvement in fuel efficiency.

In addition to CUVs, the new transmissions will also be used in two other cars early next year, likely to be the refreshed Fusion and Milan sedans which use the same engines as the Escape. Ford plans to shift almost all of their automatic transmissions to new six speeds over the next few years. By the end of 2009, they intend to build over 1.4 million vehicles with six speed automatics, double the current amount. By 2012, 98 percent of their North American transmissions will be six speeds. The new 6F35 is also referred to as the 6F mid-range and although Ford officials wouldn't comment on future products, queries about a 6F low-range for the Focus and Fiesta were met with a smile.


  • The new 6F35 front-wheel-drive transmission is the latest example of Ford's powertrain technology that increases fuel economy and lowers CO2 emissions.
  • The new 6-speed debuts in the 2009 Ford Escape and Mercury Mariner sport-utility crossover vehicles.
  • Advanced automatic transmissions represent one part of Ford's comprehensive strategy to improve fuel economy and deliver sustainable solutions for customers.


DEARBORN, May 7, 2008 – Ford Motor Company is fitting the 2009 Ford Escape and Mercury Mariner with the automaker's newest, advanced 6-speed automatic transmission, further demonstrating its commitment to reduce greenhouse gas emissions and improve fuel economy for customers.

The new 6F35 front-wheel-drive transmission offers a 4 to 6 percent improvement in fuel economy versus conventional 4- and 5-speed automatics, in addition to improved acceleration.

"With a greater gear span, the 6F35 allows the engine to operate at more optimum combinations of speed and load to meet certain driving conditions," said Craig Renneker, chief engineer for new automatic transmissions, Ford Powertrain Operations. "The new transmission also enables the engine to run at lower speeds on the highway, which aids fuel economy."

The 6F35 will be mated to a new 2.5L I-4 engine and a power-improved 3.0L V-6 in the 2009 Escape and Mariner. The engine offers horsepower increases of 17hp for the I-4 and by 40hp for the V-6, while also boosting fuel economy by 1 mpg when mated to the new six-speed transmission. The 2009 Mazda Tribute also will feature the 6F35, as will two other vehicles early next year.

The new 6-speed offers numerous technologies and design features that increase durability, performance and quietness. Ford's patented one-way rocker clutches allow for smoother, quieter, more precise shifts. Working like a socket wrench, the rocker clutches spin freely one way, but securely lock in the other direction. As result, gears are engaged and disengaged more quickly.

Other notable features include:

  • Chain-driven secondary gearset – Specifically designed with random-size links, the unique chain reduces noise, vibration and harshness when driving the transmission's secondary gearset.
  • Unique pump-filter interface – Virtually eliminates pump whine, contributing to projected best-in-class noise, vibration and harshness characteristics.
  • Flat-tow capability – Vehicles equipped with the 6F35 can be flat towed (all four wheels on the road) behind other vehicles without damaging the transmission. When flat towed, the transmission is in neutral, but internal parts rotate, causing heat. With the engine turned off during towing, the pump cannot create pressure to move oil around in the transmission and cool parts. To address this, internal baffling was added to the 6F35 to capture and direct oil to key areas.
  • Fluid fill for life – A special blend of transmission fluid is maintenance free for the life of the gearbox.
  • Transmission System Characterization – A process that utilizes software to ensure proper transmission operation before a vehicle leaves the assembly plant. During final testing, the functioning of several common shift cycles are matched against established parameters. Variability is then corrected by software in the Powertrain Control Module. The process helps deliver a high-quality, correctly operating transmission to customers from the very first day they drive their new vehicle.

Quality Tested for Durability
Ford automatic transmissions are subjected to hundreds of hours of durability, noise, vibration and harshness (NVH) testing. A series of accelerated durability trials equate to 150,000 miles of the most abusive customer usage under extreme conditions.

"One test for the 2009 Escape was to run in fourth gear with maximum trailer load at 100 mph for 15 miles. And that was repeated about 500 times," explained Rich Rej, 6F35 systems engineer, Ford Powertrain Operations. "We determine what the most abusive driver would do to our transmissions and then we do more to it to make sure that we are delivering a high-quality, durable gearbox for our customers."

Ford also utilizes a state-of-the-art Transmission NVH Hemi Anechoic Chamber that allows engineers to develop hardware to meet noise and vibration targets that will result in a quiet, interior cabin, and yield higher customer satisfaction levels for transmission quietness.

The new 6F35 6-speed automatic transmission is assembled at Ford's Van Dyke Transmission Plant, which also produces the 6F50 6-speed automatic in 2008 models of the Ford Taurus, Taurus X, Edge, Mercury Sable, Lincoln MKX and 2009 Ford Flex and Lincoln MKS.

Ford 6F35 front-wheel-drive, 6-speed automatic transmission:


Van Dyke Transmission Plant (Sterling Heights, Mich.)


Sharonville Transmission Plant (Sharonville, Ohio)


2009 Ford Escape
2009 Mercury Mariner
2009 Mazda Tribute

[Source: Ford]

Share This Photo X