MDS.. on or off?

[Jack.]

Done a bit of research here and there, seems like the opinion is split 50/50. Some think MDS will cause engine failure in the future and some say it doesnt. Do you guys drive with mds on or do you just buy an adapter to turn it off?

 

[theblet]

I leave it on. If you want to disable it just hit the + on your steering wheel when you hit 8th gear.

 

[Jack.]

I leave it on. If you want to disable it just hit the + on your steering wheel when you hit 8th gear.

Mines on as well. Just curious to see whether or not anyone actually have had "engine problems" with mds being the cause

 

[SD Rebel]

I'm not sure either, I've seen videos for both, most recently that it actually helps with upper valve-train lubrication. But on older MDS systems, there is some evidence it causes issues, not sure if that applies to the system we have now.

However, what you are not likely to get issues from MDS operation if you don't use it. If you turn off MDS, your truck should operate at a baseline function that is free from any issues that MDS could potentially have. That doesn't mean you won't get a roller pin issue or broken manifold bolts, but that's another conversation.

 

[Jack.]

I'm not sure either, I've seen videos for both, most recently that it actually helps with upper valve-train lubrication. But on older MDS systems, there is some evidence it causes issues, not sure if that applies to the system we have now.

However, what you are not likely to get issues from MDS operation if you don't use it. If you turn off MDS, your truck should operate at a baseline function that is free from any issues that MDS could potentially have. That doesn't mean you won't get a roller pin issue or broken manifold bolts, but that's another conversation.

Yeah, ive read about the valve train lubrication as well. Thats actually was an interesting read considering the process of MDS you would assume would give the opposite effect LOL

 

[Shives]

What older MDS version? Pre-DT? Curious. Thanks.

 

[HSKR R/T]

I'm not sure either, I've seen videos for both, most recently that it actually helps with upper valve-train lubrication. But on older MDS systems, there is some evidence it causes issues, not sure if that applies to the system we have now.

However, what you are not likely to get issues from MDS operation if you don't use it. If you turn off MDS, your truck should operate at a baseline function that is free from any issues that MDS could potentially have. That doesn't mean you won't get a roller pin issue or broken manifold bolts, but that's another conversation.

I'd say the issue with.not using MDS would be that you still have the MDS lifters that would still fail the same whether you use MDS or not

 

[jeffjcalweb]

it's much better than 4th gen (I had a 2015 1500 5.7). I almost don't even notice it now, so I leave it alone. I did see in AlphaOBD a few settings that sure looked like it could be turned off but I am not going to experiment and find out lol.

 

[SD Rebel]

I'd say the issue with.not using MDS would be that you still have the MDS lifters that would still fail the same whether you use MDS or not

That's a good point. But would they work better if being used? As in being more lubricated?

 

[SD Rebel]

Yeah, ive read about the valve train lubrication as well. Thats actually was an interesting read considering the process of MDS you would assume would give the opposite effect LOL

I know right? I would expect the other way, but apparently when in MDS it causes oil to pool in the upper parts of the valvetrain, where the Hemi doesn't lubricate as well as other engine designs.

Though it doesn't work when idling, which is where you need the oil the most on the top of Hemi engines. But in reality, who knows for sure?

 

[bigdodge]

off all the time

 

[Andymax]

On all the time.

 

[Florida RAM]

I prefer to let the engine operate as designed.

 

[Richard320]

Mine goes in and out of ECO mode so smoothly, that if I disabled the light and didn't have instant fuel economy displayed, I would never know. So I leave it on.

Tow/haul I use quite a bit, when I drive up in the Angeles Forest. It prevents gear hunting on the uphills and does that auto-compression braking for me on the downgrades.

 

[fishslayer]

My 17 Hemi was definitely noticeably when it went into MDS at low speed, if fact I complained to DEALER about it. They claimed it was because I used 5W20 Synthetic.. So they filled it with 0W20 blend... MADE NO DIFFERENCE AT ALL!...so I usually turned it off and refilled with 5W20. however the new truck with E-torque is nearly unnoticeable . Its so smooth ,unless you watch the ECO light, you dont feel it. So I leave it on and i am getting great MPG in town driving. BTW, I never had any valvetrain issues on my old one.

 

[Darksteel165]

Mine goes in and out of ECO mode so smoothly, that if I disabled the light and didn't have instant fuel economy displayed, I would never know. So I leave it on.

Tow/haul I use quite a bit, when I drive up in the Angeles Forest. It prevents gear hunting on the uphills and does that auto-compression braking for me on the downgrades.

I wonder if that's a 3.21 gear thing.

Mine bangs loud on the highway when going out of mds.

Also if you are on a flat road with mds on, hit the gear selector once so it turns mds off it doesn't change gear but mds will go off and your instant fuel economy barely moves, sometimes 1 mpg but generally when it's already showing like 30 or whatever.

I get better mpg with mds off epically with cruise control on. It's all about how you drive. I tried to use it for the pros, but there just aren't any so I can it tuned out. There's nothing wrong with a v8 running on all cylinder.

Lifters will still probbly blow up, but could be 50k miles, or 150k miles. I wonder if these ones are as bad as the GM lifters for their version of mds. Those were common to blow up under 60k miles even the current generation had a recall with dealerships being forced to replace lifters on delivery on new vehicles before they were even sold.

 

[HSKR R/T]

I wonder if that's a 3.21 gear thing.

Mine bangs loud on the highway when going out of mds.

Also if you are on a flat road with mds on, hit the gear selector once so it turns mds off it doesn't change gear but mds will go off and your instant fuel economy barely moves, sometimes 1 mpg but generally when it's already showing like 30 or whatever.

I get better mpg with mds off epically with cruise control on. It's all about how you drive. I tried to use it for the pros, but there just aren't any so I can it tuned out. There's nothing wrong with a v8 running on all cylinder.

Lifters will still probbly blow up, but could be 50k miles, or 150k miles. I wonder if these ones are as bad as the GM lifters for their version of mds. Those were common to blow up under 60k miles even the current generation had a recall with dealerships being forced to replace lifters on delivery on new vehicles before they were even sold.

I have 3.92s. I never knew if the MDS was on or off until I turned on the eco light. Had to have radio off to even notice a difference in exhaust. And that was with the Borla ATAK

 

[Bpebler]

I wonder if that's a 3.21 gear thing.

Mine bangs loud on the highway when going out of mds.

Also if you are on a flat road with mds on, hit the gear selector once so it turns mds off it doesn't change gear but mds will go off and your instant fuel economy barely moves, sometimes 1 mpg but generally when it's already showing like 30 or whatever.

I get better mpg with mds off epically with cruise control on. It's all about how you drive. I tried to use it for the pros, but there just aren't any so I can it tuned out. There's nothing wrong with a v8 running on all cylinder.

Lifters will still probbly blow up, but could be 50k miles, or 150k miles. I wonder if these ones are as bad as the GM lifters for their version of mds. Those were common to blow up under 60k miles even the current generation had a recall with dealerships being forced to replace lifters on delivery on new vehicles before they were even sold.

I just came from a 21 with 3.21 into a 22 with 3.92 but I could still always feel the MDS kick off - not every single time, but enough that I didn’t like it. I did a few commercial roof inspections for warranties for a contractor in TN & he told me that both of their 5th gen Ram 1500’s had issues at the 5th cylinder from the MDS kicking on and they were both between 55k-95k so that was enough for me to keep it off. I drive about 60k per year for work though, so it’s a bit more prevalent of an issue in regards to how I use my truck. I just hit the -/+ on the steering every time - no plug in accessory to disable it, although I’m interested in the Banks Pedal Monster over the Pedal Commander, but that’s a different conversation.

 

[theblet]

Mine isn’t noticeable at all

 

[Orion10182011]

I've wondered about this. I can turn mine off with HP Tuners. But since a MDS failure is usually the lifter roller locking up, I don't see how disabling MDS will prevent that.

I'm running Mobil 1 oil, I figure that will do more to keep the issue at bay then disabling MDS.