6F50 Archives - Transmission Digest
Friendly Rivalry Builds Success

Four years later, the results of the collaboration were two very similar (though slightly different), highly efficient, 6-speed transmissions. They boasted a 4% increase in efficiency over similar vehicles with automatic 4-speeds. Ford decided to name their models 6F50 and 6F55, while GM decided on 6T70/6T75/6T80. Ford has used their transmissions in the Edge, Taurus and Escape, to name a few; while GM has used them in the GMC Acadia and Terrain, and Chevy Impala and Traverse.

Trading Places

Most builders swapping hard parts have learned that mismatching drive components in a transverse unit will result in a host of negative consequences. The wrong ratio sprocket(s) or carrier can result in TCC and ratio codes, along with converter and unit clutch slippage. Unfortunately, optional ratios aren’t exclusive to the final drive; they can exist in the valve body as well.

GM 6T30 Six-Speed Automatic – Junior Addition – Part 1

During development, the GM 6T70 and Ford 6F50 basically fell off the same sheet of paper resulting in a noticeable amount of interchangeability of various components. One key difference between the two models is that GM chose to go with a mechatronic (TEHCM) valve body design, whereas Ford stuck with the traditional external TCM (PCM). Another variable between the GM and Ford transmissions were the dreaded cushion springs that have been tweaked over the years. Both designs accommodate the larger vehicles equipped with higher output engines and both have received continuous changes and upgrades.