Do you like your MDS?

[Firebird]

I keep MDS turned off in town, and only use it for hwy travel. The transition is too abrupt in the 5th gen, couldn't even feel it in my 4th gens.

 

[StuartV]

I keep MDS turned off in town, and only use it for hwy travel. The transition is too abrupt in the 5th gen, couldn't even feel it in my 4th gens.

I couldn't feel it in my 4G and don't feel it in my 5G.

 

[Blackhawktech]

The MDS on my 2013 was a lot smoother than my new truck. Driving at 45 I both hear it and feel it jerk when i gently step on it. Sometimes it shudders slightly. Is there any dealer adjustment for that?

I hate the MDS system and I think it’s bad for the engine!

 

[SD Rebel]

I honestly don't like only half the cylinders working, not sure how that translates to wear. But I can't feel a thing when it's on or off. I can only tell by my Eco light which I finally decided to activate so I see when it turned on. Still can't hear or feel it.

I am installing a custom Flowmaster Outlaw on Monday, so maybe I'll finally be able to hear it when it drones on 4 cylinders.

 

[StuartV]

My ‘09 with a Hemi had MDS. I bought it new, hammered it pretty much all the time, towed a 28’ camper trailer up and down the East Coast, and traded it in with 193K miles on it. Never had a lick of trouble with the engine or transmission. Just changed the oil when the EVIC said to, and flushed the tranny and changed the spark plugs once each.

If MDS is bad for the engine but helps on mileage, I will take that trade off.

 

[rceagle1a]

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.

Were the 4th gen trucks you drove 6sp or 8sp? There lies the biggest difference between the two.

 

[SpeedyV]

Were the 4th gen trucks you drove 6sp or 8sp? There lies the biggest difference between the two.

No idea. The biggest difference I noticed was that the loaners (complimentary Enterprise rentals) were very basically equipped trucks, e.g. 2WD Big Horns with no optional features, so they were also a lot lighter than our loaded rigs.

 

[sjsleuth]

Guess I'll have to drive around with the windows open an radio off to see if I hear anything... I really don't feel anything (aside from the ****ty up/down shifts after coasting)

change your muffler you'll here it.

 

[DraKhen99]

I drove on a bunch of flat land recently on a family vacation, and I was surprised how much time my truck spent in MDS mode... 4k on the clock, Adaptive Cruise On. It was really nice, and hardly noticeable. Pretty sure I could only tell because with the wife and kids in the truck, I had the radio volume on 6 to 8 and all the windows up.

I'm a happy camper - the eTorque + MDS equaled 19 mpg (lie-o-meter, haven't refilled yet and done hand-calculation).

-John

 

[MJB4450]

I'm a happy camper - the eTorque + MDS equaled 19 mpg (lie-o-meter, haven't refilled yet and done hand-calculation).-John

Not trying to start an argument but I would really like if someone did a long trip with MDS and the same exact trip without. Just having MDS on does not mean it's saving gas. Your mileage seems to support my findings that MDS makes no difference. My test was driving a week to work and back with MDS and the same route, speed, weather etc without MDS when I had my 2015 with 3.92 gears. This was combined city/hwy but mostly hwy. I was getting 19 mpg hand calculated either week, i.e. MDS had no effect. I am not a fan of MDS so other then that period I never used it. A couple years ago I went from Tucson to Denver and back, cruise set for 75 the whole way with some city driving too and I had a hand calculated MPG of 19.8 MDS off. I am of the opinion that MDS may have a bit of an effect on the shop test loop to satisfy the Feds but in the real world no so much.

 

[MJB4450]

I honestly don't like only half the cylinders working, not sure how that translates to wear.

It does cause vibrations in the engine. On the early few years of the Challenger with the 5.7 they had many timing chain breakage on the automatic trans cars (manuals do not have MDS) because when in MDS mode the vibration caused the timining chain guide which was plastic, to break off. They eventually beefed it up to an aluminum guide. I assume the Ram always had the better guide otherwise we would have seen failures there too. But it just proves that MDS does cause additional stress to the engine. I always turned it off on my Ram anyway.

 

[Gman]

It's known that the MDS causes vibration which is why the ATMMs exist.. As to whether or not it's 'destructive', I'm no expert.

 

[SpeedyV]

It does cause vibrations in the engine. On the early few years of the Challenger with the 5.7 they had many timing chain breakage on the automatic trans cars (manuals do not have MDS) because when in MDS mode the vibration caused the timining chain guide which was plastic, to break off. They eventually beefed it up to an aluminum guide. I assume the Ram always had the better guide otherwise we would have seen failures there too. But it just proves that MDS does cause additional stress to the engine. I always turned it off on my Ram anyway.

What year was that? The HEMI was extensively updated in 2009, and it was specifically engineered for MDS (as opposed to add-on systems used by some parties).

 

[MJB4450]

What year was that? The HEMI was extensively updated in 2009, and it was specifically engineered for MDS (as opposed to add-on systems used by some parties).

2009 to part of 2012. They first tried a nylon guide to replace the hard black plastic. That didn't work so they finally went with the aluminum with a nylon friction surface. All well since then.

 

[SpeedyV]

2009 to part of 2012. They first tried a nylon guide to replace the hard black plastic. That didn't work so they finally went with the aluminum with a nylon friction surface. All well since then.

It looks like the timing chain guide problems and recall only applied to the HEMI version used in the Challenger, Charger, and 300. I suppose this confirms that a different timing chain guide was used on the Ram. There are other differences between the engines; for example, the Ram version uses an active intake manifold. Hopefully we’ll have nothing to worry about!

 

[AartWessels]

Funny, I enabled the eco-light, but have never seen it in the 2500km I have driven the truck. Not sure if it's related to me driving on LPG, or has a different reason, but so far, I have never seen it switch to ECO.

 

[Lize]

Funny, I enabled the eco-light, but have never seen it in the 2500km I have driven the truck. Not sure if it's related to me driving on LPG, or has a different reason, but so far, I have never seen it switch to ECO.

I was speaking to some one a few weeks ago who has had his converted to LPG, I never thought to ask about the MDS, would have been interesting to know. You'd expect to have seen the Eco light even if not for very long so sounds like the LPG means the MDS doesn't kick in, perhaps a deliberate setup of some sort?

 

[Gman]

The fueling system would have to be setup to work with MDS. Wouldn't surprise me if the LPG conversion isn't refined enough to support it.

ETA: After doing some reading, it appears that the feasibility would be dependent on the LPG fueling system used. If it's a single point gas injection system, probably wouldn't work at all. If it's a multi-point sequential injection system, it would have to support MDS.

 

[AartWessels]

The fueling system would have to be setup to work with MDS. Wouldn't surprise me if the LPG conversion isn't refined enough to support it.

As far as I'm aware, MDS should normally work with LPG as well. I think 80% of trucks sold on this side of the Atlantic are running on LPG, and the expertise on LPG installations is here.
I'm mostly wondering if I need to wait for a bit higher mileage before the MDS will activate, or that it should have normally worked from the start. When reading this forum, I got the impression that it differs a lot when people first see the MDS kicking in?

 

[Gman]

As far as I'm aware, MDS should normally work with LPG as well. I think 80% of trucks sold on this side of the Atlantic are running on LPG, and the expertise on LPG installations is here.

I guess I should have used my psychic powers to have known that? There's nothing evident about your location. Since you were speaking of "2500km", I was assuming Canada.

If you've enabled the ECO notification display, you should see it. It seems to come on more often as the truck breaks in, but it's noticeable even when the truck is new.