Cylinder deactivation? 5.7

[TA5thGen]

5.7L I’m new to ram. Is there supposed to be cylinder deactivation at certain speeds and should you see an eco icon in the dash cluster or something similar?

 

[devildodge]

5.7L I’m new to ram. Is there supposed to be cylinder deactivation at certain speeds and should you see an eco icon in the dash cluster or something similar?

There are a few threads on this to explain more.

Yes there is. And yes you should.

The 5.7 does have MDS and does deactivate cylinders.

It does have an eco icon. Some say they don't see it til after break in, some say they see it often, some say they rarely see it.

Some say you have to turn it on, others say it is always on.

 

[Neurobit]

There are afew threads on this to explain more.

Yes there is. And yes you should.

The 5.7 does have MDS and does deactivate cylinders.

It does have an eco icon. Some say they don't see it til after break in, some say thethey see it often, some say they rarely see it.

Some say you have to turn it on, others say it is always on.

^^^ This ^^^

My ECO icon was not turned on from the factory. It's easily done from the UConnect menu.

 

[Gondul]

^^^ This ^^^

My ECO icon was not turned on from the factory. It's easily done from the UConnect menu.

I also had to go into the settings and turn on the icon...

 

[Jus Cruisin]

I also needed to turn the eco on in uconnect. I rarely saw it on until I reached 1,300 miles. I did a 1200 mile trip right out of the chute. Now the eco lights up a lot (4,900 Miles) .

 

[dswoboda2120]

Mine comes on quite a bit and I have less than 600 miles on it. But to be fair I’ve driven it like a grandpa so far, well mostly.

 

[Mason1217]

5.7L I’m new to ram. Is there supposed to be cylinder deactivation at certain speeds and should you see an eco icon in the dash cluster or something similar?

Use the search function for keywords, plenty of info on this already. Just FYI

 

[User_3336]

I absolutely HATE *MDS* and turn it off everytime I put my truck in drive using the +/- buttons on the steering wheel.

 

[MSchnLoneStar19]

I absolutely HATE *MDS* and turn it off everytime I put my truck in drive using the +/- buttons on the steering wheel.

Why do you hate it?

 

[Twoamen]

Both my 2014 and now 2019 MDS systems, I have never been able to tell it was an option. I have never sensed the change in engine operations speed, or shifting. Since these observations are mine , maybe the systems needs adjusted if your are noticing the MDS system.

 

[XDBrad]

I absolutely HATE *MDS* and turn it off everytime I put my truck in drive using the +/- buttons on the steering wheel.

Right there with you. Why some ask? Mine has a noticeable transition coming out of MDS mode and makes a weird noise as the other 4 cylinders light off. For those who know aircraft it sounds like an APU with bad igniters and lights off late. My guess is that there is unburnt fuel in the exhaust manifold ignighting. Not a “bang” sound but more of a hollow “thump”. Happens every time it comes out of MDS.

When I take it in for the first oil change I’ll ask the service rep to take a look but until then, I’ll hit the gear limit switch and just do away with the issue.

 

[cjmst23]

I also needed to turn the eco on in uconnect. I rarely saw it on until I reached 1,300 miles. I did a 1200 mile trip right out of the chute. Now the eco lights up a lot (4,900 Miles) .

OK, I'm missing it. Please let me know where in the uconnect (12.1) I can find this option. Thx

 

[Gondul]

OK, I'm missing it. Please let me know where in the uconnect (12.1) I can find this option. Thx

Pg 614 in the Manual.

Settings ---> Display ---> Fuel Saver Display. On/Off

 

[Ramlax]

I as well dislike this feature, I just put a flow master catbsck exhaust on and when it activates there is a terrible drone

 

[cjmst23]

Pg 614 in the Manual.

Settings ---> Display ---> Fuel Saver Display. On/Off

Geez.... I guess looking under DISPLAY made too much sense for me. Thx!

 

[User_3336]

Could not have provided a better explanation myself!!! At slower speeds, say 40-45, it appears sluggish while in MDS (like you are truly driving a 4cyl in a truck), and the "hollow thump" is a very accurate desription of the sound. at highway speeds I some seem to notice it. I have just got into the habit of using the +/- to disable it.

The "AFM" in the GM trucks is noticeably worse (similar to MDS in ours). It is a pronounced "bang", and in some models it was causing excessive oil consumption.

Right there with you. Why some ask? Mine has a noticeable transition coming out of MDS mode and makes a weird noise as the other 4 cylinders light off. For those who know aircraft it sounds like an APU with bad igniters and lights off late. My guess is that there is unburnt fuel in the exhaust manifold ignighting. Not a “bang” sound but more of a hollow “thump”. Happens every time it comes out of MDS.

When I take it in for the first oil change I’ll ask the service rep to take a look but until then, I’ll hit the gear limit switch and just do away with the issue.

 

[Ramlax]

I really don’t want to me shifting the truck when I drive it with the +/-, I wonder if I push the tow mode button it will deactivate the engine from using mds

 

[SpeedyV]

I lug the truck around town in MDS at 40-something mph on purpose. With the factory exhaust, it only deepens the exhaust note. I do notice a low-frequency “burp” when it exits MDS, presumably as it reignites the additional 4 cylinders.

 

[DeanKing]

I turned it on in settings. I have less than 500 miles s it comes on a lot. I hated it in my SRT but it seems to work really well in the truck. Never noticed it but I do drive pretty mild.

 

[dswoboda2120]

Right there with you. Why some ask? Mine has a noticeable transition coming out of MDS mode and makes a weird noise as the other 4 cylinders light off. For those who know aircraft it sounds like an APU with bad igniters and lights off late. My guess is that there is unburnt fuel in the exhaust manifold ignighting. Not a “bang” sound but more of a hollow “thump”. Happens every time it comes out of MDS.

When I take it in for the first oil change I’ll ask the service rep to take a look but until then, I’ll hit the gear limit switch and just do away with the issue.

Mine is exactly the same. So many people say they can't tell. My has some vibration when active and makes that sound you describe when the MDS kicks off.