Do you like your MDS?

[AartWessels]

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.

Thanks
The psychic powers would be very helpful, though I added some context as I was aware I might not have been clear enough.
I'll also add my location to my profile, that helps.
Based on what you wrote, I guess it's best to ask the dealer to check during the next oil change.

 

[Lize]

I guess it's best to ask the dealer to check during the next oil change.

Yes, I’d ask your LPG installer (or dealer if same person)on the type of setup he has used and whether MDS should work. Although it may not stay on for long I would expect to see MDS regardless of mileage if your system is designed to operate with it.

Think LPG is better on the continent, in the UK I’m afraid I hear too many horror stories of LPG installations by supposedly experts to be brave enough to have it done and I bought it expecting low mpg.

 

[AartWessels]

Here on the continent it’s much more common indeed, and a proper installation depends a lot on the experience and qualifications of the installer.
Bought the truck to use for our project in the UK though. Or Scotland, to be more exact.

 

[Lize]

Here on the continent it’s much more common indeed, and a proper installation depends a lot on the experience and qualifications of the installer.
Bought the truck to use for our project in the UK though. Or Scotland, to be more exact.

Check where you can get LPG along your route if you haven't already, its not that common at filling stations, think quite a few Morrisons supermarkets with filling stations do it plus some calor gas/fuel suppliers do which could be cheaper than a big brand petrol station.

 

[StuartV]

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

I know how to turn the MDS light (the one that shows ECO on the dash) off, but that does not turn MDS off. That just controls whether the light comes on or not when MDS is active.

How do you actually turn MDS off?

 

[MJB4450]

How do you actually turn MDS off?

Hit the trans down button (-) so that the custer reads "8". It will act as a normal eight speed trans but never engage MDS.

 

[StuartV]

Hit the trans down button (-) so that the custer reads "8". It will act as a normal eight speed trans but never engage MDS.

Ah. Yeah, I knew about that one. I thought you were talking about something that turned it off until you turned it back on. I.e. where it would stay off even if you turn the truck off and back on. Anyway, got it now.

 

[airgas1998]

Ah. Yeah, I knew about that one. I thought you were talking about something that turned it off until you turned it back on. I.e. where it would stay off even if you turn the truck off and back on. Anyway, got it now.

oh I wish there was a way to permanently disable it. can't even find a tuner that can do this...

 

[airgas1998]

oh I wish there was a way to permanently disable it. can't even find a tuner that can do this...such a pita when you have a locked pcm.

 

[StuartV]

oh I wish there was a way to permanently disable it. can't even find a tuner that can do this...

So odd to me. On my '09 and on my '19, I never could and cannot tell when MDS is active unless I look down and see the ECO light (or Fuel Saver on my old truck) light on.

Do you have an aftermarket exhaust of muffler? Or is it bugging you with a stock exhaust? If it's bugging you with a stock exhaust, it seems like something that should be fixed under warranty.

 

[silver billet]

So odd to me. On my '09 and on my '19, I never could and cannot tell when MDS is active unless I look down and see the ECO light (or Fuel Saver on my old truck) light on.

Do you have an aftermarket exhaust of muffler? Or is it bugging you with a stock exhaust? If it's bugging you with a stock exhaust, it seems like something that should be fixed under warranty.

Either some of us are more in tune with what the truck is doing, or it's just more noticable in some trucks than in others; but in any case, in my truck when the MDS disengages, I feel a "fish bite" effect, a tiny little tug. I don't feel it engage, just disengage, and it's more noticable than when the transmission downshifts. Once you know it's there, it's kind of an OCD thing and it just tends to drive me nuts on longer trips, and to be honest, I doubt the gas savings are significant anyway. I also feel the truck loses steam and it's harder to maintain speed while it's active, causing me to press on the pedal a little more and then the tug kicks in again.

Not the end of the world, but with all the tech and features in this truck already, would be nice to be able to permanently opt out of the system. I'm most definitely NOT a fan of it

 

[silver billet]

I also wonder if it would have been better to design the MDS for 6 cylinders instead of 4, especially in these heavy trucks. Seems to me 4 cylinders just can't keep it active long enough to make a difference, and it's cycling between 4 and 8 all the time. Perhaps 6 cyclinders would do a better job of remaining with it active, and actually getting some gas savings. Then again, the pentastar isn't really all that more efficient than the hemi either so.......

 

[Gman]

I don't notice it going in an out frequently, but that's probably due to eTorque.

 

[Rampat]

I don't notice it going in an out frequently, but that's probably due to eTorque.

I think you might be spot on here. I have eTorque and am the most OCD person I know. Most of the time I can't tell at all, I only notice if I have the radio off and hear it.

 

[Gman]

I think you might be spot on here. I have eTorque and am the most OCD person I know. Most of the time I can't tell at all, I only notice if I have the radio off and hear it.

Yep. If I have it really quiet inside, I can hear a little burble from the exhaust when it disengages, but that's it.

 

[Lize]

I feel a "fish bite" effect, a tiny little tug. I don't feel it engage, just disengage

I happened to notice this on mine earlier on, I found I could make it do it by being very very gentle on the throttle, if I accelerated as normal or quite aggressively then it doesn't do it.
Almost as if it thinks it wants to come out of MDS but hesitates due to low throttle then disengages as you carry on.

 

[StuartV]

I don't notice it going in an out frequently, but that's probably due to eTorque.

My 09 did not have eTorque and I could not tell with it, either.

 

[Gman]

My 09 did not have eTorque and I could not tell with it, either.

Transmission was also different on the '09, so I'm not sure it directly applies here.

 

[SD Rebel]

If I didn't have my aftermarket exhaust then I wouldn't mind it, it is essentially seamless operation with the stock muffler.

However, with an aftermarket exhaust, different story, it creates an irritating drone when MDS is on. No wonder the stock muffler is the size of a oil drum.

 

[SD Rebel]

I also wonder if it would have been better to design the MDS for 6 cylinders instead of 4, especially in these heavy trucks. Seems to me 4 cylinders just can't keep it active long enough to make a difference, and it's cycling between 4 and 8 all the time. Perhaps 6 cyclinders would do a better job of remaining with it active, and actually getting some gas savings. Then again, the pentastar isn't really all that more efficient than the hemi either so.......

Essentially MDS is only on when coasting or in a straight line at light throttle, the second you put any real load it turns off. I suspect with 6 cylinder operation, it's not needed since MDS isn't supposed to be active with load and at least 4 cylinder will save some fuel.