[Tomeygun]

Let this be the official 68RFE tuning thread


Admittedly I dont know a ton about tuning the 68RFE past shift points and some of the tricks for the convertor lockup... BUT I did confirm how to get 4th gear lock to act like it does in T/H mode:

(from the other thead)
I really like how when in the tow/haul mode, the convertor locks 100% immediately when going into 4th gear. so back months ago I copied over all the 4th gear convertor values from "T/H" to the regular maps. It worked, but the "locking" came after the shift. I wanted it like the t/h mode where it came DURING the shift. (PS - I started with stock trans values to learn with)

Finally got it the way I wanted when I noticed that the trans tuning on T/H mode actually commands 3rd gear lock just slightly before shifting. In other words you gotta mess with 3rd gear to achieve the 4th gear lock like I wanted.

Obvious to pro tuners... but I wanted to post this for newbs that may not have known.

Now It makes me want to revisit 3rd gear lock at WOT.

 

[jud77]

It won't lock in 3rd or 4th under wot conditions.Been tried by many people something in there goes into don't hurt me mode and it won't lock till 5th.

 

[rjp]

To this day i know of zero that have been able to make the 68 converter lock if you go WOT from a dead stop, Unless you install a manual lockup controller.

 

[BigCE]

To this day i know of zero that have been able to make the 68 converter lock if you go WOT from a dead stop, Unless you install a manual lockup controller.

Ditto, I can get it to lock in 2nd threw 6th but not at WOT

 

[davematthews]

AND WE HAVE ALL TRIED!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Promise..

One thing I want to caution in here. There has been files floating around for some time on transmission tuning. You better understand exactly what it is that your changing before putting it in the truck. The transmission is no where near as durable as the engine. One wrong file and the drive around the block could toast your od's... I've seen it happy and more than once...

The trans is something that most if not all should leave alone IMO..

 

[Tomeygun]

I just wanted 4th gear to lock like it does in tow haul mode... And that worked.

 

[Tomeygun]

To this day i know of zero that have been able to make the 68 converter lock if you go WOT from a dead stop, Unless you install a manual lockup controller.

You mean until 5th gear right?

 

[rjp]

AND WE HAVE ALL TRIED!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Promise..

One thing I want to caution in here. There has been files floating around for some time on transmission tuning. You better understand exactly what it is that your changing before putting it in the truck. The transmission is no where near as durable as the engine. One wrong file and the drive around the block could toast your od's... I've seen it happy and more than once...

The trans is something that most if not all should leave alone IMO..

This is a biggie!!!! Ive seen it, and done it myself. The biggest issue i see is usually there is no rhyme are reason of why it did what it did. I mean you can simply adjust something that you want to change and end up with something that changed that leaves you scratching your sack.:rof

 

[rjp]

You mean until 5th gear right?

All depends. Some will lock in 5th and some 6th. Mine would lock during the 6th gear shift,

 

[rjp]

If I can ever figure out how to turn this one little thing off in the TCM I think it will solve a whole lot of problems.

 

[Tomeygun]

This is a biggie!!!! Ive seen it, and done it myself. The biggest issue i see is usually there is no rhyme are reason of why it did what it did. I mean you can simply adjust something that you want to change and end up with something that changed that leaves you scratching your sack.:rof

I'm open to learning, that's why this sub-forum was made. Tell us something you changed that caused some sort of damage so we can learn from it.

Regarding 4th gear lock at WOT (from a stop)... Maybe it cant be done. and maybe 100s have tried and failed.. But I recall being told by EVERYONE that we could not control pilot injection duration, must less on the fly. Yet I did, and posted a video to prove it. Thus 12valve SOTF was born


Sometimes things that no one has done... just means that no one figured it out, not that its impossible.


PS - I'm referring to locking in 3rd or 4th at WOT... NOT shifting while TC is locked

 

[rjp]

If i could i would! Unfortunately theres still allot of information thats tied to current R&D with Suncoast.

 

[cummins96]

With my revmax 850 and in tow haul when I mash on it from a stop it will lock up in third mid way just before 4th and quickly jump into 4th locked up.


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[Michigandodgeguy]

Hey Dave.. Still want my tcm lol... I think you forgot again.. No biggie I drive around it right now, just don't wanna hurt it

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[rjp]

With my revmax 850 and in tow haul when I mash on it from a stop it will lock up in third mid way just before 4th and quickly jump into 4th locked up.


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As you raise the power this will change.

 

[cummins96]

As you raise the power this will change.

Yea I'm not running injectors or turbos yet lol. Just got mcc tuning few days ago but got shipped out of town for a few weeks. Can't even try it out lol. Wonder how the transmission will shift with daves tunes compared to box tunes.


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[rjp]

I can assure you its not 100% locked in third gear....

 

[rjp]

Yea I'm not running injectors or turbos yet lol. Just got mcc tuning few days ago but got shipped out of town for a few weeks. Can't even try it out lol. Wonder how the transmission will shift with daves tunes compared to box tunes.


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It will shift how he tells it to shift.To a certain extent!!S:

 

[cummins96]

Well I'm going by mini max gauge. When it shifts into third under full throttle just before you think it will shift into 4th it feels like it shifts another gear but it says it's locked up and jumps up in rpm. Kind I hard to explain. When I'm back in town I will take a video. It's for a split second just before it locks into 4th gear.


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[rjp]

When it locks it does the opposite. Thats the typical shifting strategy of the tranny.