Cummings Performance Variation based on Transmission

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DCD3500

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New to the forum and new to Dodge trucks. Just purchased a 2018 3500 Bighorn with the Manual Transmission. Always wanted one. I have been looking at HP / Torque values and the Manual Tranny has the lowest rating while the Auto trannys are much higher. A friend stated the difference is the clutch in the manual. The engine is detuned because the clutch can't handle the higher HP and Torque. Here are two question
1-If I put a more robust clutch in the truck, can the engine be tuned to the higher stock HP. Does anyone know how the manual engine was detuned.
2- if the engine was tuned to put out the rated HP and Torque that the Auto's put out. Does that void the factory warranty?
 

Tim Garceau

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I’ll get in on this because of curiosity.

I presume the ECM Logic/waste-gate limits boost levels to make the manufacturing process as flexible as possible for all configurations.

With warranty any modification the dealer/OEM deem the cause of premature failure would void any related coverage. Even if you swapped in another OEM control module(H.O. Aisin) to get full engine capability in a powertrain not originally designed for it.

I will say, some FCA dealers are now performance oriented and may allow a bit of leeway with 1000 horsepower cars and 1K torque trucks leaving their lots.
 

BossHogg

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New to the forum and new to Dodge trucks. Just purchased a 2018 3500 Bighorn with the Manual Transmission. Always wanted one. I have been looking at HP / Torque values and the Manual Tranny has the lowest rating while the Auto trannys are much higher. A friend stated the difference is the clutch in the manual. The engine is detuned because the clutch can't handle the higher HP and Torque. Here are two question
1-If I put a more robust clutch in the truck, can the engine be tuned to the higher stock HP. Does anyone know how the manual engine was detuned.
2- if the engine was tuned to put out the rated HP and Torque that the Auto's put out. Does that void the factory warranty?

In 2009, the RAM nameplate became its own brand. Dodge no longer makes trucks.

For the Cummins powered RAMs, there were three calibrations offered base on the type of transmission in the truck. If you want to change the output of your engine you will need to go to a tune. I know a popular option is EFILive but there are others. I don't know if you can beef up the clutch enough to hold the power a Cummins can generate. Likely one of the reasons a manual transmission is no longer offered. Any changes you make will likely void the warranty on the driveline.
 

stevehhll

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I had an '03 5.9 with the 6 speed manual. The output shaft from the xfer case was a common problem - it couldn't handle the torque. That might be why the manual xmission on the 6.7 is detuned. I definitely lost a lot of fuel economy - going from 20 mpg to about 16 mpg with my new truck. I'm thinking of checking out tuners for the mpg increase when I'm not pulling my trailer.
 

Dennis Shellito

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The only way to increase the hp/torque of your truck is with a tuner/programmer, having said this be very careful of what tune you install if you go this route as some tunes give too much pre-ignition timing which can and probably will compromise the head gasket. You will need at least a dual disk clutch to help handle the extra torque. I have heard good thinks about Valair DD clutches that work well behind a Ram Cummins. Somebody is making a triple disk clutch for these trucks but I don't know anything about them. Even with a better clutch, the operator needs to be somewhat careful on the skinny pedal.
 

392DevilDog

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The manual transmission is only rated to the torque of the Low output diesel.


In the 2nd gen the opposite was true. The automatic limited the torque. To get the HO you had to get the Manual.

It also was limited...why the V10 never got a power boost.

So, the 4th Gen Manual Cummins is derated due to the transmission. And of course...it is now gone.
 

Power247

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The clutch is the weak spot in the G56 manual trans. Once you upgrade the clutch you can add power, within reason of course.

Tuning is the only way to really add power. Tuning only voids warranty if you have a power train problem that can be proved to be caused by the tuning. But in the end it is up to the dealership so you really want to check with them before adding tuning.

Greg
2012 | RAM 2500 | CCSB | Custom tuned by Double R Diesel
2016 | Heartland Pioneer | DS310
 

tjfdesmo

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The dual mass flywheel and the clutch need upgraded. Talk to Southbend Clutch. But, most importantly, there is no "G" in Cummins.
 
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