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MDS and how to disable it?

Ram19Va

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I'm looking for a way to disable MDS, as the new exhaust note when it kicks in does not sound right. Now I'm running 87 octane, and I drove 150 miles via Interstate most of the way and through some towns, and I averaged almost 19mpg. I purposefully drove so that if the MDS kicked in I would accelerate right away to measure how good mpg I would get without it. With the new Carven Competitor you can clearly hear it kick on and off(Specifically sounds like a low reverberating hum that is loud).
Around 2,700 miles atm, and I had E-Torque off for the trip. The most I have seen on the truck is 19.7mpg. So to me w/o MDS your not losing any real mpg.

I have read about a permanent method where a Ram tech hooks up a scanner tool and just makes a simple selection to turn MDS off. Wonder how much that would cost though....
The temporary method seems to be use the + and minus symbols on steering wheel. Not sure if I have this right, but if you select 8 that will turn MDS off and the vehicle will shift automatically as usual....just MDS is turned off? I believe you have to be in drive when you do it.

Another side note on MDS, and I don't understand this, but when it kicks on it seems the vehicle actually loses speed/power at cruise to a point where it causes you to use the gas again within 10 seconds or so. Not sure if anyone else experiences the same thing.

If anyone has more info on disabling for 2019's please share.
 

Ram19Va

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I figured it out quite a while back. I just use gear selector to disable it every-time I drive. Haven't used MDS in about 2 months, and I enjoy the truck better.
 

SD Rebel

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I heard that MDS actually helps with oil lubrication, though not sure. Either way, I got use to letting it drone when in MDS, in the past it would bother me, now not so much now. You can also turn it off by leaving your truck in Tow/Haul mode as well, though that will decrease your mpg by the more aggressive shift scheme.

Make sure to have your Eco light activated, so you can see it when MDS is active. While you are at it, turn on your "Current Gear" option in your gauge settings, so you can see whatever gear you are in all the time. That indicator, when activated will show up to the right of the PDRN in the gauges. When you use your gear limiter option, that will now appear to the right of the current gear indicator.
 

mikeru82

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Another side note on MDS, and I don't understand this, but when it kicks on it seems the vehicle actually loses speed/power at cruise to a point where it causes you to use the gas again within 10 seconds or so. Not sure if anyone else experiences the same thing.
This is an effect I haven't seen. MDS was pretty noticeable on my previous truck, so I always disabled it using the shift limit buttons. But on my current truck I wouldn't notice it most of the time if the ECO light wasn't enabled. The cruise control holds speed within 1 mph of setting. MDS kicks out before I notice any decrease in speed. Based on that, I don't bother disabling it on this truck. It sounds like there may be an issue with yours based on your description of what you have been seeing.
 

asgadf/lkjnadsfg

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when it kicks on it seems the vehicle actually loses speed/power at cruise to a point where it causes you to use the gas again within 10 seconds or so.

It "seems" to lose power, or it actually does lose power?

The way the MDS works is that when it de-activates the four cylinders, it increases fuel to the remaining cylinders to continue down the road at the same level of power...otherwise you wouldn't be able to maintain the same speed.

If you are saying your truck is losing speed when it comes on, then it would seem that you have a problem.

On the other hand, if you just don't like the idea of MDS, and you've talked yourself into thinking it's losing power, then the problem isn't the truck, it's the driver. :ROFLMAO:

Below is a link that describes in great detail what your MDS is doing, and how it does it.

https://www.motortrend.com/how-to/chrysler-5-7l-hemi-mds-lifters/
 

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