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Aisin transmission and defueling in the lower gears 1-2-3 ??

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4th to 5th gear 18 68rfe

Loud “Fan?” After startup

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They have to reduce torque in the lower gears or you will damage the drivetrain. Unlimited torque in 1st gear would be 4030 lb/ft to the rear axle. The driveshaft, u-joints, and axle are not large enough to handle that, so they torque manage in lower gears.

I kinda disagree. I think it should handle the power. The tires will slip before damage. Ford doesn't seem to limit power very much. Then you factor in the low range on a 4x4 and the torque converter, you are talking some serious torque to the drive train.

I don't know what the AAM is rated at but I would think it is as much or more than a Dana 80. The D-80 is rated 10k intermittent tq and 2500 continuous.

On my 68RFE, I don't notice much delay from a stop, the power it there. What I do dislike, is the transmission is unsure what to do more often than not. If you use cruise, touch the brake and push the throttle all very quickly, the transmission is like, what?? Any quick throttle input off/on, the transmission doesn't know if it should down shift or upshift. I miss my standard at times like this.
 
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I kinda disagree. I think it should handle the power. The tires will slip before damage. Ford doesn't seem to limit power very much. Then you factor in the low range on a 4x4 and the torque converter, you are talking some serious torque to the drive train.

I don't know what the AAM is rated at but I would think it is as much or more than a Dana 80. The D-80 is rated 10k intermittent tq and 2500 continuous.

The tires won’t slip easily if you’re at the RAWR.

The COT and MOT you listed include the ring and pinion torque multiplication. If the D80 has 4.10’s in it that means the torque rating at the driveshaft is only 610 lb/ft. A HO can do 677 lb/ft in 6th gear.

The AAM 12.0 is certainly stronger than the D80, but I don’t know the specs on it.

What u-joints are on the current HO’s?

The Fords I’ve driven seem to limit power too and they even have a smaller axle on some 2500’s. I haven’t driven a d max in a long time.
 
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Everybody can feel the torque management as the acceleration rate stays more or less the same, no matter which gear you are in. On my old Gen 3 it is obvious if it shifts from 3th to 4th at WOT, it does not slow down as one would expect. Same in low range, different ECM mapping there. If that engine would be truly unleashed it would turn the drive train into mush within a blink of an eye.
 
I noticed yesterday that not much braking with th off I wouldn’t let my wife or someone that did not really under stand how it works th and xbrake. It can be very abrupt on some tight cash 99 degree corners etc. I told her she needs to drive it just drive it normal . My old truck was really hard for strangers to drive and understand . Torque converter locked and lighted toggle switch on right side knee bolster. My step son just could never get it figured out
 
If that engine would be truly unleashed it would turn the drive train into mush within a blink of an eye.

I think you are underestimating the quality of Dodge/Ram running gear. I have seen a 100 Diesel sled pullers with stock drive trains running 800hp/1200tq Ford, Dodge and GM. It is rare to break. My brother has a Big block 556 in his '78 F-250, 1200hp/800tq running a d-60 front and d-70 rear, pretty small in comparison.

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I think you are underestimating the quality of Dodge/Ram running gear. I have seen a 100 Diesel sled pullers with stock drive trains running 800hp/1200tq Ford, Dodge and GM. It is rare to break. My brother has a Big block 556 in his '78 F-250, 1200hp/800tq running a d-60 front and d-70 rear, pretty small in comparison.

View attachment 133317 View attachment 133318

Pretty cool, how heavy are these trucks?
 
Pretty cool, how heavy are these trucks?

This class (pro stock) is 6200 lbs. Note the slight bow in the bed, the sled puts hurt on you:) The tow chain is short and hooks to the bottom of the sled and 26" up, on the truck. I have seen him power completely out with his 700 hp motor in the super stock class.

This guy is not stock as you can tell:D The "pinky truck", but shows the power of the diesels. They can vary from 400-2000 hp depending on the class.

 
Well, I missed a test drive when the Cinder Block Cummins were introduced in Indiania to the group. But I was told there was no or little torque management at a standing start and they would smoke the tires at will.
 
At the last May Madness I believe it was? I test drove a 19 DRW with the AISIN. I hammered it and it felt exactly the same as my 15 with aISIN. All I heard about the truck is it would smoke the tires, NOT!!! So it sure did have torque management no different as mine.
 
From what I’ve seen in the OE programming they most certainly limit power, maybe they don’t call it torque management anymore as a method of advertising… but it does the same thing.
 
So I have complained about this in years past, even had my local manager call his inside guy who confirmed it is indeed a programmed in feature. He thinks that the tanny is not that weak but that they dont want to have to warranty transmission at 99K due to someone stomping on it for 5 years....I can kind of see his point but mine has been the following

We buy a diesel truck for a reason, if the motor has higher output then match it to a transmission that can last and not have to have this much programmed lag in it. I actually think it is dangerous myself. People are not as nice driving these days and if you get out there and lag they aren't slowing down...their being asses.

My 2003 5.9 took off the line more linear, no lag. It didnt have as powerful of an engine or as good as my aisin but I dont see any reason why it could leave the line better than my 2017. so some programming seems reasonable but not in the situations I am in where my 5.9 could safely get into or cross traffic without having to plan for the 3 second lag.

I have a smarty that removes a lot of this but I am running stock programming at this time. They certainly could of dialed this in more acceptably to match the stronger transmission
 
I am hearing people pleased with the 2022. I wonder if they lightened up on the programming due to complaints and they are more comfortable with time letting more power be put to the wheels. If they did they probably would not tell us as we would be standing in line for a reprogram :)
 
I really think is a learning curve. Plenty of power to pass merge into traffic. Etc. it just a different sensation You step into the throttle not slam it to the floor. The ho with the aisin is not a dead beast. Just different.
 
So I have complained about this in years past, even had my local manager call his inside guy who confirmed it is indeed a programmed in feature. He thinks that the tanny is not that weak but that they dont want to have to warranty transmission at 99K due to someone stomping on it for 5 years....I can kind of see his point but mine has been the following

We buy a diesel truck for a reason, if the motor has higher output then match it to a transmission that can last and not have to have this much programmed lag in it. I actually think it is dangerous myself. People are not as nice driving these days and if you get out there and lag they aren't slowing down...their being asses.

My 2003 5.9 took off the line more linear, no lag. It didnt have as powerful of an engine or as good as my aisin but I dont see any reason why it could leave the line better than my 2017. so some programming seems reasonable but not in the situations I am in where my 5.9 could safely get into or cross traffic without having to plan for the 3 second lag.

I have a smarty that removes a lot of this but I am running stock programming at this time. They certainly could of dialed this in more acceptably to match the stronger transmission

The transmission is just one aspect of the drivetrain. The rest can't handle that much torque. U-joints, driveshaft, and axles are are too small to handle full torque in any gear. The drivetrain required for full torque in 1st gear would be too large an impractical for a pickup. With the torque multiplication of the TQ converter, trans ratio, and rear axle the full torque simply isn't needed in lower gears.

My 18 is more linear and has less lag than my 05 did with stock programming. I don't notice any lag in my 18 HO or dads 17 HO, maybe it's driving style, but nothing to note...especially 3 seconds of lag.

The 03 certainly limited torque as well. You did not have full torque/power in lower gears.
 
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I am hearing people pleased with the 2022. I wonder if they lightened up on the programming due to complaints and they are more comfortable with time letting more power be put to the wheels. If they did they probably would not tell us as we would be standing in line for a reprogram :)

I drove the 2020's and compare them to the 2019 and 2018. The 2020's would immediately slip the tires on throttle input during takeoff being a night and day improvement over the delays in the 2018 I have. I simply drive around it on the 2018 and WILL NOT step out in traffic when the situation requires immediate acceleration not "accelerate when it feels like it": Because it won't. I have had to bail on the brakes after it's delay is over and it decides to get moving as traffic has suddenly changed like a last second 3 lane change from oncoming traffic before an intersection. :mad:

Only the HO was acceptable to me going from a 2003 MT in the 2018/2019. Mostly dump the clutch and stall saver got it moving N O W on the 2003. The 2018 delay from a dig or step out of the way at 65 MPH ... I said the heck with a new RAM until I drove the HO. You got traffic merging and a choice to be ahead or burning the brakes behind to let them in, more than one in a line of vehicles being ahead is sometimes the best choice for smooth traffic flow.

IMO It wants the proper turbo setting, rail pressure, and the proper gear before rolling on power. Even the 2008 Duramax we had would take time to get back on it if you let off say aborting a pass then using the passing zone after it cleared up a moment later. Going off the rails I read where improvements to the actual rail itself can help with delays getting the power on.

Fun tip of the day: Powerbraking through a turn just to keep the power "on" and avoid it's delays getting power back on will trip the stuck accelerator nanny protection mode. Then you got No Power. :eek:
 
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