Eco Mode does not work at altitude(above 6400ft elevation)

[easymoney]

Hi All,
My truck is a 2022 1500 5.7. Since the truck was new the eco mode has not worked above 6400ft. but works as expected below 6400ft.
It's not user error.(the eco mode in my 2018 ram worked fine everywhere) 2 dealerships have told me they can't help me. I only rarely get to elevations low enough for the eco mode to work.
Has anyone else noticed this condition? Is it Normal? Is it fixable?
Thanks for your help,

 

[GKIII]

There are too many variables here to give any sort of sure answer. How much heavier is the 2022? Same engine? Same rear gear? Different years tune the MDS system differently? Do you have tow/haul on?

Any time I've been above 6400 feet I'm on a mountain so the MDS only kicks on when going slightly downhill and not towing anything

 

[HSKR R/T]

Hi All,
My truck is a 2022 1500 5.7. Since the truck was new the eco mode has not worked above 6400ft. but works as expected below 6400ft.
It's not user error.(the eco mode in my 2018 ram worked fine everywhere) 2 dealerships have told me they can't help me. I only rarely get to elevations low enough for the eco mode to work.
Has anyone else noticed this condition? Is it Normal? Is it fixable?
Thanks for your help,

Probably normal. There is reduced power at higher altitudes which may prevent eco mode from coming on.

 

[Bt10]

As stated above, this is normal, BUT, fill in your sig line with truck specs and people can give you more definite and quicker answers to some of your questions. That said, I have the best possible chance at eco, and rarely ever see it, except as said, slowing or downhill.

I'm sure it helped Ram get thru EPA cert'ing, that is all. Sad advertising hype, because in theory, the truck should have 395hp / 2, - extra rotating motor drag = should be what, 170hp? A lot of trucks in the 80's didn't have 170hp at WOT and could still hold 80mph. Well, ok, at 11mpg. But still...

 

[WasatchBack]

I live at 7k feet and MDS works fine, even kicks in climbing up the 600 foot hill to my house if I'm gentle on the throttle, as well as at 10k in nearby mountains

 

[easymoney]

Thanks for the ideas and input,
I've had this truck 10 months now watching all the variables and the one that is always the same is altitude. Every time I drop below 6400 the MDS starts working.
I don't think it's normal. sorry to be in disagreement but I've seen plenty of other trucks, thanks WasatchBack, around with working MDS systems.
Last spring, The dealership in my town told me I was the third guy to come in with a 2022 complaining their MDS didn't work at our altitude. He told me Ram would come out with a fix, but I just talked to him again and nothing from Ram yet.
The truck has plenty of power. If they were going to lock out the MDS at altitude it seems like 10k would be a better point.
It seems like the problem is a bad air sensor(like the air sensor that controls the EFI settings) sending the wrong information to the computer. Or the computer settings themselves. Neither of which should be a problem to change.
What do you think? Who do I talk to to get something from someone at Ram that knows for sure what's going on?

 

[MDNT2021]

I have a 2021 1500 5.7. I live at 7k and travel up to 10k+ I have had no issues with the eco mode. Works just fine art all altitudes. I think the bad air sensor or clogged air filters would be great places to start.

 

[Darksteel165]

I have eco mode turned off.
The additional wear on the engine for a non-existent increase in mpg isn't worth it to me.

 

[Timeless]

@easymoney curious what octane gas you are using.

I've noticed that the 87 (85 is available at those altitudes) uses eco mode far less than the suggested 89....I'm assuming due to the timing/performance hit.

 

[easymoney]

I use the 85 octane gas most of the time. I only put 89 in if I am towing or will be towing a heavy load so it's mixed in my tank. Good idea! I'll start running all 89 so it becomes straight 89 and see if that changes anything.

 

[Runagun]

I have eco mode turned off.
The additional wear on the engine for a non-existent increase in mpg isn't worth it to me.

Explain the additional wear part. Cause as I recall it's just having fuel cut off to the cylinders.

 

[HSKR R/T]

Explain the additional wear part. Cause as I recall it's just having fuel cut off to the cylinders.

The lifters also hold the exhaust valves open so there is no compression in those cylinders

 

[Jimmy07]

The lifters also hold the exhaust valves open so there is no compression in those cylinders

That is actually the exact opposite of how MDS works.

 

[HSKR R/T]

That is actually the exact opposite of how MDS works.

I am probably wrong. I know the lifters lock out, and figured keeping valve open made the most sense so there isn't the resistance from compression on a dead cylinder

 

[CogitoErgoLevo]

this article explains MDS

What Is Hemi MDS?

We explain how Chrysler Hemi MDS cylinder deactivation works, what goes wrong, and how to fix it when it breaks.

www.motortrend.com