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Do you like your MDS?

silver billet

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I dont think so, my truck goes into eco every time i set my foot off the brake. According to the light, I am spending 75% with the mds on.
I have been reading about it, but there is no definitive answer to settle it, is the eco light MDS or not.

Maybe the "classic" and older generation is different?

But in my truck, the eco light is tied 100% to MDS. Three different signals that MDS is active: I see the light, I feel a little "fish bite" (sometimes), and I hear a change in the exhaust sound. Those 3 happen always at the same time. I don't always feel the fishbite, but when I do it's instantaneous with the other 2 signals. The other 2 (light + sound) are always happening at the same time. After 1800 KM's on the dial and paying attention to this ECO/MDS stuff like a hawk (even setting my main dash to the eco display), to me that is definitive.
 

SpeedyV

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Maybe the "classic" and older generation is different?

But in my truck, the eco light is tied 100% to MDS. Three different signals that MDS is active: I see the light, I feel a little "fish bite" (sometimes), and I hear a change in the exhaust sound. Those 3 happen always at the same time. I don't always feel the fishbite, but when I do it's instantaneous with the other 2 signals. The other 2 (light + sound) are always happening at the same time. After 1800 KM's on the dial and paying attention to this ECO/MDS stuff like a hawk (even setting my main dash to the eco display), to me that is definitive.
Absolutely agree on both points. I've driven 4th-gen loaners that practically live in "ECO" mode, and I'm not sure if it's tied to MDS. But in my truck, like you, there has never been a time when the ECO light has come on where I haven't felt MDS kick in. They are explicitly linked.
 

Rampat

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I have zero issues with mine. I actually never noticed it until reading about aftermarket exhaust choices and people complaining about hearing MDS. Then I listened hard and found it. I don’t feel it. I turned on the ECO light option on the cluster and that’s how I know I’m in it or not. Usually I drive normally and let it kick in when it can but sometimes on the highway I like to play the game and see how long I can keep in MDS. So far I’ve been able to get it to hold up to 78 mph for a decent 5-8 miles at a time on flat Florida Highway.
 

silver billet

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Absolutely agree on both points. I've driven 4th-gen loaners that practically live in "ECO" mode, and I'm not sure if it's tied to MDS. But in my truck, like you, there has never been a time when the ECO light has come on where I haven't felt MDS kick in. They are explicitly linked.

FCA doesn't really help matters, since ECO means different things across different products. In my Pentastar Jeep GC, I would also get an "ECO" light on my display, which had nothing to do with cylinder deactivation since the v6 didn't have that option; ECO just meant you were hardly pressing the gas pedal (as far as I could tell anyway).
 

Gman

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The setting for displaying ECO in the instrument cluster is defined as "Fuel Saver Display in Cluster". The manual defines the following;
FUEL SAVER TECHNOLOGY 5.7L ENGINES ONLY — IF EQUIPPED This feature offers improved fuel economy by shutting off four of the engine's eight cylinders during light load and cruise conditions. The system is automatic with no driver inputs or additional driving skills required.

ECO = Hemi MDS
 

Granite5thgen

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I could feel and hear the MDS every time, even more so after my muffler install. I turn it off the second I put the truck in drive. Averaging almost 17 mpg and I'm not that light on the throttle
 

silver billet

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I could feel and hear the MDS every time, even more so after my muffler install. I turn it off the second I put the truck in drive. Averaging almost 17 mpg and I'm not that light on the throttle

I was reading a different thread here which suggests that being too easy on the pedal is worse for MPG; takes too long to get up to speed, so less time spent at lower RPMS + using MDS. There is probably a lot of truth to that, the trick is finding out exactly how firm on the skinny pedal you should be to max out MPG.
 

Granite5thgen

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I was reading a different thread here which suggests that being too easy on the pedal is worse for MPG; takes too long to get up to speed, so less time spent at lower RPMS + using MDS. There is probably a lot of truth to that, the trick is finding out exactly how firm on the skinny pedal you should be to max out MPG.
Yeah I try to get the truck to shift about 2700-3k til about 62-65 (55 mph around where I live) then I let out and drive from there. Usually shifting in 5th or 6th when I get to that speed, then it drops into 8th and on flat ground at 65 I'm around 21 on the dash
 

Wakesnowb

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I turned on my ECO light a few months ago. I must say that I see the light come on and do not notice anything else other than the fact I am not really pressing the pedal. Other than that I would not even know the MDS is kicking in. Seems pretty good to me and I like it so far :) Of course I am not sitting there trying to scrutinize it much either, just seems to work seamlessly for me so far.
 

J-Cooz

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Compared to the 6.4 in my previous SRT this MDS is smooth as silk. In the 6.4 you could hear the exhaust change and it vibrated the car. When it would kick off be exhaust would make a pop. It was very annoying. I can barely hear it on the new ram.
 

StuartV

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My MDS engages/disengages completely smoothly; I'd never notice if it wasn't for the ECO light. What I do notice is a bit of engine braking when the transmission downshifts while coasting.

I have noticed what felt like engine braking as well. I thought it was a bit odd. When I read your post, something clicked in my head and I wonder if it's not the eTorque system doing some regenerative braking to generate some electricity for charging the eTorque battery pack.


As far as MDS goes, I had an '09 (4th Gen) 1500 with a Hemi. Now I have a '19 with a Hemi and eTorque. Both with 3.92 rear ends.

I have never heard or felt either truck going in or out of MDS. In my old truck, it would show "ECO" or something like that in the EVIC. In the new truck, I enabled that display setting on the first day. My old truck went in and out of ECO a lot. The new truck goes in and out. In both cases, I can only tell because I see the indicator in the dash display.

I pretty much always have music playing. I only ever hear my engine in the new truck when I'm at least somewhat "in it" on the gas. My old truck was a "Sport" - i.e. had the sport-tuned factory exhaust. I could hear the engine more, for sure, in the old truck. But, with both trucks, I have never heard any change when going in or out of ECO mode.

Since I have never heard or felt it, I reckon I like MDS. At the very least, I don't think it's hurting my mileage....
 

ppowell1983

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I had it in my 2018 Ram Rebel and I noticed it and it was slightly annoying. My 2019 limited, I don’t even notice it.


Sent from my iPhone using Tapatalk
 

saxapl

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MDS is unobtrusive in this truck. In my wife's SRT Durango you certainly know it is happening. Of course, it is in MDS a lot more often because the 6.4 has excess horsepower. The 5.7 needs all 8 more often.
 

Turin

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I have noticed what felt like engine braking as well. I thought it was a bit odd. When I read your post, something clicked in my head and I wonder if it's not the eTorque system doing some regenerative braking to generate some electricity for charging the eTorque battery pack.
I didn't get eTorque on my truck so that's not what I'm experiencing. I did test drive a truck with eTorque, though, and the regenerative braking does have a similar feeling; just more pronounced.
 

SD Rebel

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I have zero idea if MDS is actually on or not, not sure if the Eco light is tied directly to it. I see the light on when I'm cruising and light on the throttle, but don't notice anything by feel or sound. I think when I get my upgraded exhaust I may finally hear something different.
 

SD Rebel

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It is. The green ECO light means that MDS is active and you're running in four cylinder mode.

That's good to hear! OK, I'll pay closer attention to it, but my Rebel's exhaust note is so quiet, especially with the windows up, I have a hard time noticing anything.
 

ddharris

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Funny, you always here Ford and Ram guys saying that... Chevy guys are too far back to hear what they're going on about. :ROFLMAO::cool:

MDS works flawlessly for me. Getting up to speed quickly is also a key then let it go into ECO mode by letting up slowly on accelerator. Works great and cannot tell when it switches over unlike my 18 Silverado I traded for this truck.
 

Al Czervik

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I turn it off the second I put the truck in drive. Averaging almost 17 mpg and I'm not that light on the throttle
^^^ same here. I have a full cat back and can't stand the bogged down sound MDS makes when it kicks in. I average a pretty steady 17.5 mpg and keep my foot in it on a regular basis to enjoy that sweet Hemi tone... ;)
 

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