When Ford debuted its 6F transmission back in late 2005, we were told it could handle up to 300 horsepower and 280 lb-ft of torque. That transmission debuted with the automaker’s 3.5L V6 and both are now widely used together in a number of Ford, Lincoln and Mercury products. Times have changed, however, and Ford has introduced a new version of its 3.5L V6 with twin turbochargers and direct injection. Called the 3.5L EcoBoost, this engine makes more power than the original 6F transmission, now called the 6F-50, can handle. Enter the 6F-55, a new version of the 6F-50 with beefed up internals to handle the 3.5L EcoBoost’s 355-365 hp and 350 lb-ft of torque. One example is the new ring gear on the 6F-55 (shown at right), which is 41.5mm thick compared to 31.5 mm on the 6F-50.
[Source: Ford]
