Twinturbostroker
New member
Soooo long story short.........H&S single kit on my 6.4, took some fighting to get it on with a aftermarket DP, but she's in and sitting pretty. Have custom H&S tuning obviously, but there seems to be an issue with the 5TC coming on at 65MPH, I've had 3 tranny tunes sent and 65 seems to be the magic number. I need it to hold out to 75MPH at least, tuner seems to be having an issue getting around it???.......I have 37" and come to find out 3:55 gears, which I loved the pull with the stock set up, and 1st thru 4th are amazing under light to medium throttle with the single, but Jesus Christ does it fall on its face when it hits 65 to about 75-80, 1400RPMs just aint gonna cut it......I've been getting around it for the time being by hitting tow/haul and that will kick it down to 4TC and hold it, but that's a little much for just regular driving......if I could get 5th to about 75-78 and then TC lock, that would be perfect or at least a great starting point.....thanks fellas!!!