6.4l terrible mpg

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Fatbob Frank

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This forum is awesome...
For every thread wondering " how can I increase my mileage?" or " Why is my 4x4 so terrible on gas?" there are at least 2 threads asking " How much lift to run 40s?" or " what's the biggest tire I can run with no lift?"
 

BuschLatte420

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2022 classic tradesmen crew cab 6’4 box
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5.7L NON E-TORQUE 3.92 gears 4x4
Huge ass heavy truck, big tires, big motor, yep I think that thang is gonna be thirsty lol…when people talk about putting the truck in manual 8 to avoid MDS kicking in does it still shift like normal when it needs to or do you have to manually shift it. I never had a vehicle with this.
 

SniperDroid

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Huge ass heavy truck, big tires, big motor, yep I think that thang is gonna be thirsty lol…when people talk about putting the truck in manual 8 to avoid MDS kicking in does it still shift like normal when it needs to or do you have to manually shift it. I never had a vehicle with this.
Everything normal, but no MDS worries... when towing the camper, it's nice to have the visual indication of the gear your in.
 

BuschLatte420

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Everything normal, but no MDS worries... when towing the camper, it's nice to have the visual indication of the gear your in.
Nice, I would rather use all 8 cylinders that I paid for!
 

dhay13

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you can see my actual here vs my EVIC reading. usually within .7 or so MPG and even a few where my actual was better than my EVIC reading

1664221435500.png
 

Ratman6161

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Nice, I would rather use all 8 cylinders that I paid for!
We're it not for the little green MDS light coming on from time to time, I'd never notice the system was working. You do get all your cylinders when they are needed. Just put a little piece of electrical tape over the light and all will be well :)
 

Riccochet

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We're it not for the little green MDS light coming on from time to time, I'd never notice the system was working. You do get all your cylinders when they are needed. Just put a little piece of electrical tape over the light and all will be well :)

You must be high because I can 100% feel and hear when it kicks in and out of MDS.
 

dhay13

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We're it not for the little green MDS light coming on from time to time, I'd never notice the system was working. You do get all your cylinders when they are needed. Just put a little piece of electrical tape over the light and all will be well :)
Yeah I can tell by feel and sound for sure
 

BuschLatte420

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5.7L NON E-TORQUE 3.92 gears 4x4
you can see my actual here vs my EVIC reading. usually within .7 or so MPG and even a few where my actual was better than my EVIC reading

View attachment 503001
Seems pretty spot on with being most off by towing, 6.6 with the camper is rough lol
 

KKBB

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You must be high because I can 100% feel and hear when it kicks in and out of MDS.
I agree. I can definitely feel the shaking when it kicks in. Even makes my dash rattle right under the toggle switches for tow/haul and all the others. There is a piece of plastic that I have to push on to stop the noises from it when the 4 cylinder crap kicks in.
 

dhay13

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Seems pretty spot on with being most off by towing, 6.6 with the camper is rough lol
Our boat weighs 8900lbs, almost as much as that camper but notice how much better the MPG is with the boat. That there shows the effects of aerodynamics
 

JerryETX

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you can see my actual here vs my EVIC reading. usually within .7 or so MPG and even a few where my actual was better than my EVIC reading

View attachment 503001
I wish mine was that close. Last weekend drove 383 miles 98% highway. I kept speed around 72 the entire time (even when speed limit was 80) and feathered the pedal trying to get the best mpg possible. Evic read 17.7. Actual was just under 15.5. This is pretty typical with my truck.
 

JerryETX

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6.6 with the camper is rough lol
I get between 5 and 6 mpg according to Evic pulling our 38 foot travel trailer (about 9600 lbs loaded) and my evic is always at least 1.5 miles off so I'm likely getting worse than that.
 

RamGuy110

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I using a 22' 2500 6.4 hemi for a rental while my cummins is in the service bay, so I'm towing my trailer for work. The mileage doesn't seem to be that bad, but tranny feels very jerky. This truck has 18k on it. I've had a Ford with the 7.3 for a rental and now this....the drivability of the Ford is way beyond the Ram with the 6.4. Just MO.
 

SniperDroid

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I using a 22' 2500 6.4 hemi for a rental while my cummins is in the service bay, so I'm towing my trailer for work. The mileage doesn't seem to be that bad, but tranny feels very jerky. This truck has 18k on it. I've had a Ford with the 7.3 for a rental and now this....the drivability of the Ford is way beyond the Ram with the 6.4. Just MO.
How much weight are you pulling, and are you using the Tow/Haul mode?
 

Ratman6161

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I agree. I can definitely feel the shaking when it kicks in. Even makes my dash rattle right under the toggle switches for tow/haul and all the others. There is a piece of plastic that I have to push on to stop the noises from it when the 4 cylinder crap kicks in.
I really believe that those of you noticing a dramatic difference when MDS kicks on and off must have some kind of malfunction going on. I'm being totally honest here when I say that on mine, there is no perceptible shaking, vibration or noise. Either that or its min that's malfunctioning...i.e. MDS really isn't kicking in. but I don't think that's the case. When I see the green light come on, I also see an increase in the instantaneous fuel economy number.
 

Ratman6161

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I using a 22' 2500 6.4 hemi for a rental while my cummins is in the service bay, so I'm towing my trailer for work. The mileage doesn't seem to be that bad, but tranny feels very jerky. This truck has 18k on it. I've had a Ford with the 7.3 for a rental and now this....the drivability of the Ford is way beyond the Ram with the 6.4. Just MO.
The ford 7.3 has 46 lb/ft more torque and also a 10 speed transmission
 

dhay13

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I really believe that those of you noticing a dramatic difference when MDS kicks on and off must have some kind of malfunction going on. I'm being totally honest here when I say that on mine, there is no perceptible shaking, vibration or noise. Either that or its min that's malfunctioning...i.e. MDS really isn't kicking in. but I don't think that's the case. When I see the green light come on, I also see an increase in the instantaneous fuel economy number.
I have had 2 of them and both were noticeable. If you are coasting you won't really notice it but on flat ground at part throttle it is noticeable.
 
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