Is A Revmax 700 As Good As An Allison?

First let me say I love ALMOST everything about my 2018 2500 everything except the damn 68RFE shift quality!

Seems like every time I’m traveling about 45mph and slow to around 15mph to come around a turn, it’s stays in 3rd or 4th and slips the converter like there is no other!!! I hate that, feels like I’m burning up the transmission constantly...it starts gradually locking but it’s a very unpleasant feeling.

Truck is deleted and tuned with DRD, shift points are great and drives awesome otherwise.

Will a revmax 700 fix my issues or do I go back to a Duramax? My old truck was a 2016 Duramax, it shifted awesome! Nothing like this!

I WANT QUICK CRISP SHIFTS THAT DONT FEEL LIKE THE TRANSMISSION IS JUST SLIPPING ALL OVER THE PLACE.

I’m on a 30hp tune and don’t hot rod my truck or tow by the way.

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Originally Posted by TUNED18

First let me say I love ALMOST everything about my 2018 2500...everything except the damn 68RFE shift quality!

Seems like every time I’m traveling about 45mph and slow to around 15mph to come around a turn, it’s stays in 3rd or 4th and slips the converter like there is no other!!! I hate that, feels like I’m burning up the transmission constantly...it starts gradually locking but it’s a very unpleasant feeling.

Truck is deleted and tuned with DRD, shift points are great and drives awesome otherwise.

Will a revmax 700 fix my issues or do I go back to a Duramax? My old truck was a 2016 Duramax, it shifted awesome! Nothing like this!

I WANT QUICK CRISP SHIFTS THAT DONT FEEL LIKE THE TRANSMISSION IS JUST SLIPPING ALL OVER THE PLACE.

I’m on a 30hp tune and don’t hot rod my truck or tow by the way.

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Are you past the learning period of a few hundred miles with trans tuning? If so have you talk to Ray about what you are feeling in trans?

If yes to both ^^

A new converter should remedy the slip. I am not sure how the Allison was but I had a triple disc converter in my last truck and you would know when it would lock - it was firm. Sounds like a triple disc may be what you prefer for a low stall single disc that will grab better for you.

The problem he's referring to is the shift flare. It always seems to float in between the set gears.

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Originally Posted by TexNeck

Are you past the learning period of a few hundred miles with trans tuning? If so have you talk to Ray about what you are feeling in trans?

If yes to both ^^

A new converter should remedy the slip. I am not sure how the Allison was but I had a triple disc converter in my last truck and you would know when it would lock - it was firm. Sounds like a triple disc may be what you prefer for a low stall single disc that will grab better for you.

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I emailed ray, he suggested a low stall revmax converter and valve body.

I just want want to make sure those two items will make a difference, it’s a $2000 gamble for me at this point, I just want it to shift nice, quick and firm...I hate feeling all that converter slip and the fact that when I’m driving around at say 40mph and slow down to like 15 mph it just unlocks 4th and slips the hell out of the converter, just feels like that is not to be how it operates.

I know exactly what he is talking about. I don't think it is shift flare. I think it is the gear that the transmission decides it wants to be in.

When you slow down from a higher speed to take a turn or an off ramp the transmission consistently chooses the wrong gear... too high of a gear.
Many times Ill be on an off ramp and then go to accelerate from about 20 mph and the transmission will still be in 5th gear with the converter unlocked so it will just use the torque converter slip to accelerate until the truck is going fast enough to lock the converter in 5th. What it should do is downshift into 2nd or 3rd gear at those speeds and shift through the gears as if you were starting from a dead stop.
It truly is very annoying. If you use tow haul mode it is way too aggressive the other way. Once you get on the brakes it starts dropping gears and trying to slow down too much.
Its too bad you cant be in regular mode and slow down to whatever speed normally and then have the transmission take vehicle speed and throttle position into account and select an appropriate gear.
Many times I will just select 4th as the maximum available gear when in town to avoid this situation.
I also had an Allison / Duramax in the past and it had much more intelligent transmission tuning then what you can get for a 68RFE right out of the factory... And that was 2007 technology to boot. Ford transmissions are much smoother and more refined that the 68 as well. I drive them at work every day.
I wish I could afford to install an Allison in my truck.

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Originally Posted by Aj Grubb

I know exactly what he is talking about. I don't think it is shift flare. I think it is the gear that the transmission decides it wants to be in.

When you slow down from a higher speed to take a turn or an off ramp the transmission consistently chooses the wrong gear... too high of a gear.
Many times Ill be on an off ramp and then go to accelerate from about 20 mph and the transmission will still be in 5th gear with the converter unlocked so it will just use the torque converter slip to accelerate until the truck is going fast enough to lock the converter in 5th. What it should do is downshift into 2nd or 3rd gear at those speeds and shift through the gears as if you were starting from a dead stop.
It truly is very annoying. If you use tow haul mode it is way too aggressive the other way. Once you get on the brakes it starts dropping gears and trying to slow down too much.
Its too bad you cant be in regular mode and slow down to whatever speed normally and then have the transmission take vehicle speed and throttle position into account and select an appropriate gear.
Many times I will just select 4th as the maximum available gear when in town to avoid this situation.
I also had an Allison / Duramax in the past and it had much more intelligent transmission tuning then what you can get for a 68RFE right out of the factory... And that was 2007 technology to boot. Ford transmissions are much smoother and more refined that the 68 as well. I drive them at work every day.
I wish I could afford to install an Allison in my truck.

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You sir have just wrote exactly what my complaint is!!! I just could not articulate it that way unfortunately...

is is there a fix for this? I’m 100% annoyed with this, enough that if the 68RFE is unable to not act that way I will trade my truck in for a truck that will shift the way it should (I WANT MY TRUCK TO BE THE ONE SHIFTING CORRECTLY!)

is is it a tuning issue? Do I need a built transmission? I want an answer, I’ll dump money into it if it can be remedied.

I don't think a built transmission or a lower stall converter would solve the problem. The problem is not that the converter is too loose, the problem is that the transmission is in 5th gear with the converter unlocked when it should be in 3rd with the converter locked. The issue is not hard parts its software, the algorithm used to select what gear to be in and when.
As far as answering the question of "can it be fixed with tuning?" Well I don't know. My truck already had DRD tuning when I purchased it, I have never driven another 68RFE truck so I don't know how they drive stock or with other peoples tuning.
I suspect that the software that is used to bridge the gap between the Cummins engine and the Chrysler transmission is difficult and clunky to work with so its hard to get every little annoyance tuned out of these things. I want to say I read something about making a tuning change to get one desired result and having it cause other unintended consequences that the tuner never expected.

Ray may be able to try to tune this out for you if you ask him. I can't request that he make any changes to my tuning because I was not the one who originally purchased the tunes. If you are the original purchaser of your tunes... from what I have read here Ray will absolutely bend over backwards to satisfy his customers. Feel free to use my description of the issue above to help explain to him what you are experiencing if you like. I'm curious to see if he can fix it or not.

I'm sure if you reach out to @dudes_diesel_performance. He'll steer you in the right direction. He deals with Bilt trans and can answer your questions tcm programming. I think some come with the tuning module

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[QUOTE=Djfundamentalz;150290]I'm sure if you reach out to @dudes_diesel_performance. He'll steer you in the right direction. He deals with Bilt trans and can answer your questions tcm programming. I think some come with the tuning module

Sent from my SM-N960U using Tapatalk[/QUOTE

@Dude's Diesel Performance

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Originally Posted by Aj Grubb

I don't think a built transmission or a lower stall converter would solve the problem. The problem is not that the converter is too loose, the problem is that the transmission is in 5th gear with the converter unlocked when it should be in 3rd with the converter locked. The issue is not hard parts its software, the algorithm used to select what gear to be in and when.
As far as answering the question of "can it be fixed with tuning?" Well I don't know. My truck already had DRD tuning when I purchased it, I have never driven another 68RFE truck so I don't know how they drive stock or with other peoples tuning.
I suspect that the software that is used to bridge the gap between the Cummins engine and the Chrysler transmission is difficult and clunky to work with so its hard to get every little annoyance tuned out of these things. I want to say I read something about making a tuning change to get one desired result and having it cause other unintended consequences that the tuner never expected.

Ray may be able to try to tune this out for you if you ask him. I can't request that he make any changes to my tuning because I was not the one who originally purchased the tunes. If you are the original purchaser of your tunes... from what I have read here Ray will absolutely bend over backwards to satisfy his customers. Feel free to use my description of the issue above to help explain to him what you are experiencing if you like. I'm curious to see if he can fix it or not.

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I will definitely forward your description to him, thank you.

I am the original owner.

Mine does this same thing, can't wait to hear the solution.

I realize this is a 4-year-old post, but I wondered if anyone found a good solution.

I'm in the same boat.

I love the Cummins but tolerate the 68RFE.

Mine is a deleted 2018 with a DRD tune.

I was looking at RevMax converters and valve bodies, but I'd like to know if they will improve shifting points/shift flare etc., before shelling out the $$.

I tow about 5% of the time (usually 10-15k lbs.) so this would mainly be to improve daily driving.

Thanks.

The valve body and trans tuning helped a little, but it still does the same thing; my 68RFE seems to love 4th gear.

I have 4.56 gears that I will install at some point to get me back to lower the lower-than-stock final gear ratio, so hopefully, that will help a little more.

If you install the valve body, I don't think you can get an updated tune now to take advantage of it.