6R140 transmission - manually lock out 6th gear?

[bobby5832708]

On my 2017 29VE the 6R140 transmission shifts between 5th and 6th at about 45 to 55 mph way more than I'd like it to. If there was a way to prevent the trans from shifting into top gear (like the OD cancel button on my 2005 Crown Vic does) that would solve the problem.

The only option I can see is using the "4" position on the gear select but 4th is too low of a gear and the engine revs too much at 50 mph in 4th. Tow/haul mode helps a bit but still the trans shifts way too much between 5th and 6th on a speed limit 45 to 55 road as compared to if it was manually limited to 5th gear. Not only the annoyance of the frequent shifting but it can't be good for long term durability having the trans shifting back and forth like it does.

Is there anyone doing transmission tunes that would change the function of the tow/haul button to be an OD lockout like on the old Crown Vic? This is on the 6 speed transmission, not the older 5 speed which has it's own shifting issues.

[creativepart]

I believe 5-Star Tune will customize the tune on request. But I’m not positive.

[Bones2003]

Does it make much difference if you use Tow/Haul mode or not? All gear positions are available in tow-haul but the shift points change. Also, on my 2021 you can lockout gears using Progressive Range Selection. Check the transmission section of your Ford owner's manual to see if you have that feature. I accidentally locked out 6th gear one time and it took me awhile to figure out what I had done. Other than that, I don't think I ever would have discovered that feature!