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is there any 6.4 truck combos with no MDS from factory?

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mike_ct

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is there a trim or series with a 6.4 that does NOT use MDS??
like say a 4500 cab & chassis? are those still equipped with MDS?
do POWER wagons have MDS?
 
Not well-versed with the 6.4 gas engines, but I believe (someone correct me if I’m wrong) you can inhibit the MDS by simply putting the truck into ERS mode. Its a work-around. AFAIK, all the current 5.7 and 6.4 hemi engines come with MDS and there’s no direct option on the truck to manually shut it off or disable it, aside from the workaround I mentioned.
 
mbarber84 said:
Not well-versed with the 6.4 gas engines, but I believe (someone correct me if I’m wrong) you can inhibit the MDS by simply putting the truck into ERS mode. Its a work-around. AFAIK, all the current 5.7 and 6.4 hemi engines come with MDS and there’s no direct option on the truck to manually shut it off or disable it, aside from the workaround I mentioned.
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My 5.7 R/T Durango will go into mds unless you hit the “eco off” button in the center stack. Once pressed it stays off until it’s pressed again. This includes after shutdowns, etc. other options on my specific model are track and sport modes will also deactivate it.
 
flan said:
My 5.7 R/T Durango will go into mds unless you hit the “eco off” button in the center stack. Once pressed it stays off until it’s pressed again. This includes after shutdowns, etc. other options on my specific model are track and sport modes will also deactivate it.
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It is my understanding that ECO mode and MDS are independent functions. ECO mode changes the shift schedule in the transmission. MDS deactivates cylinders when cruising in certain conditions. Thus engaging or disengaging ECO mode will not have an effect on the MDS system. As far as I know, the only work-around is using ERS mode or Tow / Haul to trick the vehicle into shutting MDS off.

Again, I’m really not well-versed in the gas engines so if I’m wrong I would appreciate a correction!
 
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flan said:
My 5.7 R/T Durango will go into mds unless you hit the “eco off” button in the center stack. Once pressed it stays off until it’s pressed again. This includes after shutdowns, etc. other options on my specific model are track and sport modes will also deactivate it.
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Yep, I keep it turned off on my R/T as well
 
I tune mds on and off with hptuners for people vehicles, but more or less was interested if any ram factory models were not using it.
like back in ~2011, when ram 1500 + 2500's both were using 5.7's, the 1500 had ads equipment but the 2500's did not. same 5.7 block. it was more a curiosity thing if any of the HD models were not shipping with MDS.
 
mbarber84 said:
It is my understanding that ECO mode and MDS are independent functions. ECO mode changes the shift schedule in the transmission. MDS deactivates cylinders when cruising in certain conditions. Thus engaging or disengaging ECO mode will not have an effect on the MDS system. As far as I know, the only work-around is using ERS mode or Tow / Haul to trick the vehicle into shutting MDS off.

Again, I’m really not well-versed in the gas engines so if I’m wrong I would appreciate a correction!
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Eco deactivates 4 cylinders. It makes a noticeable tone change when parameters are right for it to be in eco and when it’s lagging behind accelerating and the mds kicks out it sounds like a normal Hemi again.
 
Mine didnt come with the active(?) dampers on the frame though due to the global panic politics so it makes a noticable shudder/vibration in the chassis on change too.

At least I assume those dampers help mitigate that.
 
mike_ct said:
I tune mds on and off with hptuners for people vehicles, but more or less was interested if any ram factory models were not using it.
like back in ~2011, when ram 1500 + 2500's both were using 5.7's, the 1500 had ads equipment but the 2500's did not. same 5.7 block. it was more a curiosity thing if any of the HD models were not shipping with MDS.
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I’m not aware of any 6.4 BGE’s that did not come with MDS.
My thought was, if there was possibly ever a 6.4/G56 trans combo, it might not have had MDS, but I went through the current j2534 Fed World Report list of calibrations, and couldn’t find an instance of a 6.4 PCM calibration with a G56 trans.
 
mike_ct said:
is there a trim or series with a 6.4 that does NOT use MDS??
like say a 4500 cab & chassis? are those still equipped with MDS?
do POWER wagons have MDS?
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Hello, I work at ZF and was involved in the Powerline development for 2025.

The 6.4 Hemi does not use MDS on the Chassis Cabs equipped with a Powerline transmission.

It still uses MDS on the pickup trucks with the 8HP-LCV transmission however
 
The new 2025 2500’s no longer have MDS, you can look it up under the Ram trucks build
 
DURKAN said:
The new 2025 2500’s no longer have MDS, you can look it up under the Ram trucks build
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Well I’ll be dammed. You’re right from what I can tell. Looking at a 24 vs 25 window sticker the 25 no longer says it.
 
The real question is does using the (already equipped) MDS as intended or turning it off as often as possible make any longevity difference? Is one easier on cam/lifters/valvetrain?


Sent from me
 
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