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MDS question

Buz

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I'm almost as old as dirt. Never in a rush to go anywhere. Prize gas mileage over acceleration. I drive about as tender as one can get and I never hear or feel the MDS kicking in or kicking out.

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33 gallon fuel tank, factory dual exhaust, 18” wheels. Build date: 03 June 2018. Now at: 042963 miles.
Mine must be broken then.
 

cj7

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I tried to search MDS or eco mode but nothing came up but in reality I know this must have been covered before. When I first got the truck in June it had 12k miles on it. Now I have 17k and before about 3 weeks ago I rarely if ever saw eco light on. Now it’s on all the time while cruising. Let’s say I’m going 35mph and the trucks in 6th and eco mode. The problem is I feel a slight hesitation coming out of eco mode it’s almost a little shutter and it sounds like it’s lugging the truck down. I’m not sure what to make of it. The trans seems to also be slow downshifting in this same time frame if that makes sense. I’ll come to a slow stop and still be in like 5th gear at 10mph then when I go to accelerate I feel it hard upshift to 3rd after a slight lag. Not sure what’s happening but it just started all this a few weeks ago. What’s y’all’s opinion is it the truck just getting a little more broken in? Seems weird to me might be a dealer trip

On when MDS works / ECO lights, posted this a bit ago

ECO is MDS, and comes on as follows:
- engine reaches operating temp
- tow haul is off
- no gear limit is set
- load is less than 25%, is in gears 4-8 and RPMs > 1000 (or something like that)
- stays on until load exceeds 50%, RPM drops to <1000, etc
- comes back on when load remains less than 25% for at least four seconds straight

Load is as the ECU measures it, and is reported on OBD2, CAN. Load is also RPM sensitive, not a measure of how much you‘re pushing the gas pedal.
 

PowerJrod

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I tried to search MDS or eco mode but nothing came up but in reality I know this must have been covered before. When I first got the truck in June it had 12k miles on it. Now I have 17k and before about 3 weeks ago I rarely if ever saw eco light on. Now it’s on all the time while cruising. Let’s say I’m going 35mph and the trucks in 6th and eco mode. The problem is I feel a slight hesitation coming out of eco mode it’s almost a little shutter and it sounds like it’s lugging the truck down. I’m not sure what to make of it. The trans seems to also be slow downshifting in this same time frame if that makes sense. I’ll come to a slow stop and still be in like 5th gear at 10mph then when I go to accelerate I feel it hard upshift to 3rd after a slight lag. Not sure what’s happening but it just started all this a few weeks ago. What’s y’all’s opinion is it the truck just getting a little more broken in? Seems weird to me might be a dealer trip.
Might not be the engine at all...maybe just needs a transmission update. I would bring it in for that first. Only took my service center 2 hours from bringing it in to driving off with it.
 

mikeru82

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Mine must be broken then.

I notice it on my Laramie because I have an aftermarket exhaust. I rarely noticed MDS when it still had the stock exhaust though. I never notice it in my wife's Limited. I suspect that...Buz, you have a problem. :ROFLMAO:
 
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Dusty1948

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Mine must be broken then.
Are you using a Pedal Commander or other type device?

Best Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33 gallon fuel tank, factory dual exhaust, 18” wheels. Build date: 03 June 2018. Now at: 042965 miles.
 

LakesAZ

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I'm almost as old as dirt. Never in a rush to go anywhere. Prize gas mileage over acceleration. I drive about as tender as one can get and I never hear or feel the MDS kicking in or kicking out.

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33 gallon fuel tank, factory dual exhaust, 18” wheels. Build date: 03 June 2018. Now at: 042963 miles.
I'm with you on this Dusty as I also can't feel or hear it kick in.
 

Buz

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Are you using a Pedal Commander or other type device?

Best Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33 gallon fuel tank, factory dual exhaust, 18” wheels. Build date: 03 June 2018. Now at: 042965 miles.
No. It’s just obvious to me when it bogs then kicks the other 4 cylinders in.
 
U

User_3336

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Just use the +/- buttons, put it in 8th, and forget about it kicking in. Stop bitchin' about MDS when you can control it.
 

jkm312

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No. It’s just obvious to me when it bogs then kicks the other 4 cylinders in.
I am thinking the same as PowerJrod. The software that controls your shift points in the transmission may be corrupted since the original programming. Update/remap it may smooth it out for you.
 

Buz

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POOR comparison. VERY poor. MDS is a part of the truck. Diabetes isn't necessarily a part of your life.
Maybe it wasn't the most tasteful example, but my point is when you have something that is 'controlable', it's still an inconvenience compared to not having it.
 
U

User_3336

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Anyone "inconvenienced" by MDS should have researched the HEMI engine before the purchased it.

Good thing you guys didn't buy a GMC/Chevy with AFM/DFM, you'd had to buy an OBD2 port disabler to get rid of it.
 

mikeru82

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Anyone "inconvenienced" by MDS should have researched the HEMI engine before the purchased it.

Good thing you guys didn't buy a GMC/Chevy with AFM/DFM, you'd had to buy an OBD2 port disabler to get rid of it.
Research had nothing to do with it. I wanted a v8. Good luck finding any v8 gas powered truck that doesn't have some form of this.

I've never owned a GM truck with AFM, for the very reason you mentioned. I rue the day when we won't be able to disable systems like this without voiding some warranty.
 
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skidmarc

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2020 non-eTotque Rebel here. Definitely feel what the OP is talking about. For me it’s worst around our mildly hilly 30-40 mph side roads. I can feel MDS kick in, in my bone stock truck. No problem with that. It’s when MDS turns off; slight dead spot in the pedal, then a jolt. I have been turning MDS off when I drive certain roads and the truck operates so much smoother.

Also, with these Rebels, I suspect they have different MDS activation points. I need to drive with a crazy light pedal to get it to kick in at times. It never enables over 60 mph, and I can all but assure I’m way under the 25% load mentioned earlier. I’d venture to guess the MDS window in my truck is between 10-25%. But that’s a whole different point...

FWIW: I’m a light pedal hyper-miler type.
 
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Dusty1948

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Anyone "inconvenienced" by MDS should have researched the HEMI engine before the purchased it.

Good thing you guys didn't buy a GMC/Chevy with AFM/DFM, you'd had to buy an OBD2 port disabler to get rid of it.
I was hesitant to buy the 2010 Ram 1500 because just about everyone I knew that had a Silverado/Sierra with the Active Fuel Management system were really complaining hard about it. It took me three drives in separate Rams to give me confidence in the MDS system. I will say that in my 2014 Ram with the 8-speed I would occasionally feel the MDS kicking out, but it was very, very light feeling and very intermittent.

Best regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33 gallon fuel tank, factory dual exhaust, 18” wheels. Build date: 03 June 2018. Now at: 043404 miles.
 

SD Rebel

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The only reason why I shut off MDS is because my aftermarket muffler will drone in 4-cylinder mode. There is a reason why the stock muffler looks like a oil drum. However, when MDS is operating on my truck, the slightest increase in pedal pressure, it immediately goes out of MDS. The only time with my driving style that it will stay in MDS is a straight level road at very light throttle, which is rare for me since Socal is full of hills, even the highways/freeway.
 

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