[Ratdaddy60]

TCI's current 6X does not have engine braking. I am only saying that is possible to modify a 4L80E valve body to provide engine braking with the shifter in the 4th gear position.
I've been told that TCI will soon offer engine braking as an option.

[Chris Petersen]

Originally Posted by Ratdaddy60

TCI's current 6X does not have engine braking. I am only saying that is possible to modify a 4L80E valve body to provide engine braking with the shifter in the 4th gear position.
I've been told that TCI will soon offer engine braking as an option.

No offence to you but...

Unless you have built one, and it works AND survives, you are just regurating the technical side of things with no proof, kind of like a ad in hot rod for TCI.

Do you build transmissions for a living?

Would you warentee a 6sp 4L80e?

The issue is, they took a 4sp auto, and are using the computer to do most of the work to make it a 6sp, rather than design a correct 6pd trans.

Think about it, the 4L80e, is basicly a TH400 with overdrive, very tough transmission, and been proven over the years. (from what, the 1960's?)

But then using the overdrive pack applied in different stages to get a 5-6sp, just does not make sence, if you have ever had one apart, really looked at it, and have a half-arse understanding how it works.

[Ratdaddy60]

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.