MDS

nlambert182 said:

You can turn off the ECO indicator in the EVIC display on my 2018. I have mine turned off. It's called "fuel saver display". MDS will still activate whether the light is on or not. On my 2018, MDS will still activate in tow/haul mode. The only way I can disable MDS is to manually put it in 8th gear.

I too am looking for options to tune it out. Whether or not it helps avoid the potential lifter issue doesn't matter to me.

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Disabling the ECO indicator doesn't mean you're disabling MDS. That's true in the 5th gens as well, it just means you'll never see the light show up. You're just disabling the indicator itself.

ramffml said:

Disabling the ECO indicator doesn't mean you're disabling MDS. That's true in the 5th gens as well, it just means you'll never see the light show up. You're just disabling the indicator itself.

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Yes, that was my point.

ECO and MDS are not all inclusive of each other (at least not on a 4th gen). The light can come on with MDS disabled, and MDS can come on with the light disabled.

nlambert182 said:

Yes, that was my point.

ECO and MDS are not all inclusive of each other (at least not on a 4th gen). The light can come on with MDS disabled, and MDS can come on with the light disabled.

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Where the 4th gen and 5th appear to be different: the light will never come on with MDS disabled even if the indicator light is enabled. You can turn on the indicator, drive like a grandma, use t/h or gear limiter, idle down hill - MDS doesn't come on, and neither does the indicator.

5th gen: ECO indicator = MDS mode active. But disabling indicator doesn't disable MDS itself, it just "unplugs the light from the dash".

nlambert182 said:

Yes, that was my point.

ECO and MDS are not all inclusive of each other (at least not on a 4th gen). The light can come on with MDS disabled, and MDS can come on with the light disabled.

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This is the 5th gen. subforum, you are offtopic, don't muddle things up........

ColesRAM said:

According to the article I posted (#15) that’s not necessarily true.

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Nothing against the author but they are passing along information that they heard/learned somewhere else. There's some information but a lot of it is generalities.

The author talks about "driving in a fuel-efficient way" but never defines what that is.

Also, the author says that in the 5th gen 1500 the ECO light is "shaped like a leaf". This is not true as the ECO light is a green "ECO" light on the dash, which makes me question if any of his knowledge is first-hand.

Kickboxer said:

This is the 5th gen. subforum, you are offtopic, don't muddle things up........

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Pretty sure I was clear in my post that I had a 2018.... not sure I muddled up anything?

Glen Harrison said:

Tow/ Haul does not turn off the MDS after 2019 , Manual select on the steering wheel until you get 8th gear and drive on .

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You have that backwards. T/H absolutely turns off MDS on 5th gens, which as everyone knows, have only been produced since 2019 and later. Pre-2019 are 4th gens, and on those T/H does not turn off MDS.

RC Turner said:

Why are you shutting it off ? Mine is so transparent that if it were not for the indicator on the dash I would not know it ws active.

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Why do people keep asking this? It doesn't matter why. People do things for their own reasons. Are you thinking you can change people's minds by asking why? MDS is noticeable to some, and very noticeable to others. The fact that you don't notice it doesn't mean all Ram 1500's are the same way. I've owned several Ram trucks with MDS. Some were very noticeable and others less so. But I noticed it in all of them to some degree.

DILLIGAF said:

The ECO light has nothing to do with MDS.

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Yes, it does. At least on 5th gens, which is the forum in which this thread resides. Your post is true for 4th gens and Classics, but not for 5th gens.

ramffml said:

It's not clear to me which truck some of the guys are running in this thread, could be newish classic or could be new 5th gens. But we've been through this a million times on this forum. For the 5th gen:

- ECO light = MDS active
- T/H disables MDS

4th gens work differently.

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^^This! There are many differences between 4th gens and 5th gens. The way MDS functions is simply one of those differences.

ramffml said:

Do you own a 5th gen? Because I do and I've tested it extensively; hold your speed at 35 mph, wait 2 seconds, MDS kicks in with a jerk and an exhaust note and MDS light comes on.

Flick T/H on: the truck jerks a bit, exhaust changes, and MDS light goes off.

Repeat T/H toggle 10 times in 2 minutes and note how all 3 changes always occur.

Then drive around for 5 months by always using your gear limiter in 8th gear, note how MDS light NEVER comes on. Not once.

So frankly that article is wrong. It happens.

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But...it's on the internet. Everything on the internet is true, isn't it?

Is there some type of technical/manufacturer documentation about tow/haul not turning off MDS in a 4th gen? I regularly drive on a long flat road at constant speed and either drive with or without t/h engaged. I can most certainly feel the difference as soon as I turn it off or back on. And I run through all the gears (I have a 6 speed 2500 3.73) with t/h on. I have no tuner, bought the truck brand new. There is so much confusion on this subject, I would love to have the technical documentation to understand it and to figure out why my truck reacts differently than I read from some answers given here and elsewhere. Thanks

tron67j said:

Is there some type of technical/manufacturer documentation about tow/haul not turning off MDS in a 4th gen? I regularly drive on a long flat road at constant speed and either drive with or without t/h engaged. I can most certainly feel the difference as soon as I turn it off or back on. And I run through all the gears (I have a 6 speed 2500 3.73) with t/h on. I have no tuner, bought the truck brand new. There is so much confusion on this subject, I would love to have the technical documentation to understand it and to figure out why my truck reacts differently than I read from some answers given here and elsewhere. Thanks

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I agree. Not sure why so much confusion but there is. My 2015 6.4 66rfe with 3.73 gears did the same as my now 2016 6.4 66rfe with 4.10 gears when I’m in t/h. MDS shuts off completely. Dropping down 4 cylinders would suck while towing or hauling.

buckeyexx said:

I agree. Not sure why so much confusion but there is. My 2015 6.4 66rfe with 3.73 gears did the same as my now 2016 6.4 66rfe with 4.10 gears when I’m in t/h. MDS shuts off completely. Dropping down 4 cylinders would suck while towing or hauling.

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The truck will never drop down to 4 cylinders while towing, even if it's "allowed" to (not disabled). It simply doesn't have enough torque in 4 cylinders to pull a load. Mine jerks off and on every 10 seconds on a flat road going 55 to 60 mph with very little head wind. Anything more than that and it won't every turn on at all. When I'm towing my truck is working pretty good, 2200 RPMs with being "stuck" in 6th or sometimes 7th at 1800 RPMs on the flat spots, when it's working like that it needs all 8 cylinders.

I’m thinking a lot of the confusion is comparing 6 speed 2500’s to 8 speed 1500’s as well as 4th gens to 5ths

tron67j said:

Is there some type of technical/manufacturer documentation about tow/haul not turning off MDS in a 4th gen? I regularly drive on a long flat road at constant speed and either drive with or without t/h engaged. I can most certainly feel the difference as soon as I turn it off or back on. And I run through all the gears (I have a 6 speed 2500 3.73) with t/h on. I have no tuner, bought the truck brand new. There is so much confusion on this subject, I would love to have the technical documentation to understand it and to figure out why my truck reacts differently than I read from some answers given here and elsewhere. Thanks

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buckeyexx said:

I agree. Not sure why so much confusion but there is. My 2015 6.4 66rfe with 3.73 gears did the same as my now 2016 6.4 66rfe with 4.10 gears when I’m in t/h. MDS shuts off completely. Dropping down 4 cylinders would suck while towing or hauling.

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cdn cj said:

I’m thinking a lot of the confusion is comparing 6 speed 2500’s to 8 speed 1500’s as well as 4th gens to 5ths

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You beat me to it. We have owners of 4th gen and 5th gen 1500's, as well as 2500 owners all commenting on this. They don't all work the same, so there will be conflicting posts in this thread. The OP was asking a question about a 2020 Ram 1500, but we don't know whether it's a 4th gen or 5th gen. We do know it's not a 2500 though if he's correct about it having a 5.7L.

Right, there are different vehicles. But the statement was made that 4th gen MDS cannot be turned off by t/h switch, and that appears to conflict with my experience and that of others. So while I am 4th gen and this is 5th gen forum, the ask I had was if anyone had official documentation to confirm how it works for different gens, and maybe even different levels (1500, 25/3500). This would eliminate the confusion. Not sure it exists, but seems there are some very certain people on all sides of the issue (I admit I am confused, but think I am right as to my truck's performance).

This issue is discussed so much that there should be a dedicated sticky. And this thread maybe moved to engine and performance.

tron67j said:

Right, there are different vehicles. But the statement was made that 4th gen MDS cannot be turned off by t/h switch, and that appears to conflict with my experience and that of others. So while I am 4th gen and this is 5th gen forum, the ask I had was if anyone had official documentation to confirm how it works for different gens, and maybe even different levels (1500, 25/3500). This would eliminate the confusion. Not sure it exists, but seems there are some very certain people on all sides of the issue (I admit I am confused, but think I am right as to my truck's performance).

This issue is discussed so much that there should be a dedicated sticky. And this thread maybe moved to engine and performance.

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There are plenty of older threads where this has been discussed to death. No need for another one. As far as your truck goes, it's a 4th gen 2500. The statement about t/h not disabling MDS was aimed at 4th gen 1500's. Like I said above, 4th gen 1500's, 5th gen 1500's, 2500's...they all behave a little different. This is based on information posted by owners over the years in multiple Ram forums. I'm not aware of any official documentation for this behavior. I'm sure it exists, but it may only be available to people inside the Stellantis organization.