No offense taken, but I've been in the automatic transmission rebuilding industry since 1974. I was an avid drag racer until 2004.
Ford turned the four speed 4R44E into a five speed 5R55E by changing the shift strategy. The six speed 4L80E accomplishes the adding of the two extra gears by the same method.
What's wrong with having the O.D clutch come on between the OEM 1st & 2nd gears and between the OEM 2nd and 3rd gears? The overrun roller clutch is plenty strong enough to handle this, especially if the transmission is using the 2001-up roller clutch.
The better way would be to have the overrun clutches to apply in the six speeds 1st, 3rd, and 5th gears.
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