Why on Earth do people want to disable MDS? (Hemi newb here)

Gas is cheap in my part of the world. With Mr Trump in office, it will likely stay that way for a while.

In my humble opinion, any Ram 1500 or bigger that is geared taller than 3.92 is a pity. Couple a truck that geared too tall with MDS, and that's even worse. A lot of people just push the skinny Petal, and the truck goes well enough. And that's cool. I'm a little more picky than that.

Thanks for the explanations, everyone! Maybe after I've owned it for more time I will see the light.

...And you can then decide to either keep the MDS on (or even trade it for a V6 or a mini diesel to get even better mpg) or disable it.

Let us know what is your review after a few weeks or 2-3 months...

I know my gas mileage really took a hit when I through on a Flowmaster Outlaw!
Sounds so good,I'm on the skinny pedal all the time now!

I hate it. Didnt bother me at first, but ad i drove more it started bothering me.. on the highway its great. Set the cruise at 75 and go. Around town, forget it. I hit the tow button as soon as i get in the truck now.

Don't know what the issue is with MDS. I just arrived at Disney World after a 400+ mile trip and averaged 20.3 mpg actual, the computer had it at 21. Had 3 people and bed full of luggage for a wedding. Got a '19 Laramie 5.7l with 5k miles, 3.92 gears and set the cruise control at 70. Best highway mileage I ever got with my V6 Dakota was 18 mpg. It's the person whose foot is on the loud pedal that makes the difference.

I don't know if others have found this but in our cold winter climate (Alberta), I found that driving with MDS disabled on my 14 let's the engine warm up a bit quicker. Too me this makes more sense than having fuel management operate only 4 cylinders in town in -25°C. You drive for short trips and engine & oil doesn't reach operating temperature to get rid of moisture.

Also haven't noticed any mileage difference that would make me think that the "drone" is saving me that much money... Like others I let MDS do its thing on the highway with a properly warmed up engine.

Also it just "feels" better and sounds better with it off. I like to see what gear my truck is in too which is cool. You get that only with the gear -/+ buttons.

If anyone ever comes up with a truly believable reason why MDS is going to make my motor last longer, then maybe I'll eat my words but for now, put me in the MD-not column...

Gas mileage difference with MDS is .3-.5 mpg...Almost nothing...With MDS the same 4 cylinders take the load each time MDS engages...Now I went to the public school...But even I can see that the system has to feature uneven wear at some point...It just isn't worth it...The only mode that disables it is to select the -gear each time it is taken out of park and select 8 if not already in it...Tow/Haul does not disable MDS.

I had a 13’ with mds. Soooo annoying. My 2500 5.7 does not have mds. I love that fact. She may be a little under powered and not the greatest tow machine but the ole 5.7 purrs and does what I need it to do. I consider my truck a 1500 dressed as a 2500 crew cab long bed 4x4 with a solid axle lol.

1.I get better mileage when I disable it.
2. I bought a hemi and also drive 140 miles a day for work with no actual need for a truck who gives a F*** about gas mileage lol.
3. Logic tells me that when you drop down to 4 cylinders in a 5500lb truck you wearing sh** out.

Overall think of it this way there is a reason for example the 4cyl in a ranger made it to the f150. Quick answer it wouldn't last

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Todays engines are set up to maximize mpg for government café mpg tests not for real life driving. I have no doubt that the average driver could get better mpg if the auto industry could design engines for everyday driving conditions and not for an arbitrary test. I understand that the test gives us a way to compare vehicles mpg but the government should not be mandating results and punishing manufacturers for not achieving some made up number. Free market competition will give us better mpg and lower production costs and this is almost universally true for everything. Look at all the fraud car makers commit trying to keep up with these arbitrary numbers so as not to be fined. MDS and engine stop features cannot be good for engine life but it squeezes enough mpg to satisfy the government.

^^^Thank you. Facts are that simple.

Matts175 said:

OK. So I've only had my Hemi for 6 days now. Loving the hell out of this MDS stuff! Why? Because I'm coming from a 2003 with a 4.7 that got an average of 14.6 MPG over almost it's whole life. With this new one, I'm getting a solid 15.0 (I reset it on day 1) and I now have 150 more hp (2003 4.7 is rated at 245 hp). And, I've been "punching it" a lot. I bet that'll go up to 16, once I calm down a bit. So, I'm thinking that this is all because of the MDS. Seems like a win/win. So, why are there Youtube videos/posts on here, etc. showing how to disable it? Why wouldn't you want good MPG? How does it make the truck any faster, seeing how it instantly turns on and off?

Not trying to start an argument here, just trying to gain an understanding.

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I don't understand either. I get q16.5 in town nearly all the time, and 22.5 or better on the road, empty, no towing or hauling, have had as high as 26.5 between here and Houston. So why not use it, beats the hell out of me !!!!

If you don't want to see ECO light going on and off you can just turn it off in your settings.

Matts175 said:

OK. So I've only had my Hemi for 6 days now. Loving the hell out of this MDS stuff! Why? Because I'm coming from a 2003 with a 4.7 that got an average of 14.6 MPG over almost it's whole life. With this new one, I'm getting a solid 15.0 (I reset it on day 1) and I now have 150 more hp (2003 4.7 is rated at 245 hp). And, I've been "punching it" a lot. I bet that'll go up to 16, once I calm down a bit. So, I'm thinking that this is all because of the MDS. Seems like a win/win. So, why are there Youtube videos/posts on here, etc. showing how to disable it? Why wouldn't you want good MPG? How does it make the truck any faster, seeing how it instantly turns on and off?

Not trying to start an argument here, just trying to gain an understanding.

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First let me say that I like and have absolutely no issue with the MDS system. It workes flawlessly and I have owned a 2010, 2012, 2015 all with the 5.7 Hemi with MDS and clocked an average of 160-k on each one with never an issue with the trucks. The oil and filters were changed every 4000-k and all other regular maintenance was performed on or before needed. I now own a 2019 new body style Ram Laramie 4x4 off road package with the Hemi and I really like it. Now the reason for some wanting to disable the MDS is they have installed an after market exhaust system or low restricted muffler and can't stand the sound when the engine goes from eight to four cylinders and back. It does sound like crap and I had this experience with a Dodge Challenger 5.7 Hemi with after market exhaust. I could drive on the highway at cruising speed in fifth gear instead of drive and the MDS would not kink in and out. The factory exhaust on my 2019 sounds great when you mash on it and is quite as a mouse when crushing on the highway. I have never had any of my trucks with the factory exhaust have the least amount of drone with the factory designed exhaust system. The engineers have put much time and effort in to the exhaust to ke it quite on the road but give you a nice deep tone when taking off. The thing to do is leave the factory exhaust alone and enjoy the truck.

jws123 said:

1 it saves no gas maybe like a dollar LOL
2 the lifters go bad faster and engine is noisier when it kicks in.
3 its annoying as ****.

its a failed design i took my mds 100% out of my truck put non mds lifters never goin back nor buying another mds vehicle.

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I'm sorry dude , sounds more like a flawed driver than a flawed system. Just saying.

I turned MDS off on my truck, thru the tune I installed on my 07' Quad Cab 1500, 5.7L Hemi about 3 years ago. I have a cat back exhaust system that was louder every time the MDS activated. I average 15 to 16 mpg city/highway driving. My best has been 22.2 mpg @ 75 mph Interstate travel, with cruise control activated. I have the Performance 91 SuperChips tune installed, and I run only 93 octane fuel. I use a hand held calculator to calculate my trucks fuel mileage.

I think the MDS is a “Me Too” feature. GM has it so Dodge added it to sell trucks. Or it’s there to pass EPA emissions.

As for the guy that gets 25 mph, I’m going to take that with a grain of salt.

Why did I disable MDS? Because I live in the foothills of NC and my daily drive consists of back roads up and down hills through the country. MDS was constantly kicking on and off, on and off. Disabling made if feel like a whole new truck, now the power is instantly there when I need it

If I cared about fuel mileage I'd have gotten the Pentastar... I paid for 400hp, I want it all always on!

RLJ10X said:

I think the MDS is a “Me Too” feature. GM has it so Dodge added it to sell trucks. Or it’s there to pass EPA emissions.

As for the guy that gets 25 mph, I’m going to take that with a grain of salt.

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Just to let you know Dodge had MDS on its engines two years before GM came out with it. I guess it was a me too deal but Dodge was first.