ECO mode on way too much

[WXman]

Same for me. I can't find any conclusive evidence that MDS is detrimental to engine life, but common sense says it's not helping. I deactivate it every time.

Before the 5th Gen trucks came out, there was a lot of discussion on this among the Hemi owners out there. Basically the engine failures from MDS came from two different causes. One was that when MDS is on, you've got 4 cylinder that are "cold" and 4 that are "hot" and that causes issues over time with the engine block and heads and metallurgy of the two. You've got metals contracting and expanding in different ratios inside the same block of material, and that's not good. Secondly, when MDS kicks in there is a jolt to the valvetrain. It happens so quickly on and off and on and off that it delivers a bit of a shock to the components.

The cars with this engine had a recall about ten years ago because this jolting was actually snapping the timing chain/guides and wiping out engines. The assumption was that guys with Challengers and Charger were more likely to go WOT and romp on the pedal, so those engines saw the MDS shock more severely.

Unfortunately, MDS engines have totally different lifters so removing the system requires opening the engine. On my 2011 Challenger I have MDS permanently deactivated via tune. This seems to work well. On my Ram I do what you do and turn it off by entering ERS mode every time I drive.

 

[Jako]

Before the 5th Gen trucks came out, there was a lot of discussion on this among the Hemi owners out there. Basically the engine failures from MDS came from two different causes. One was that when MDS is on, you've got 4 cylinder that are "cold" and 4 that are "hot" and that causes issues over time with the engine block and heads and metallurgy of the two. You've got metals contracting and expanding in different ratios inside the same block of material, and that's not good. Secondly, when MDS kicks in there is a jolt to the valvetrain. It happens so quickly on and off and on and off that it delivers a bit of a shock to the components.

The cars with this engine had a recall about ten years ago because this jolting was actually snapping the timing chain/guides and wiping out engines. The assumption was that guys with Challengers and Charger were more likely to go WOT and romp on the pedal, so those engines saw the MDS shock more severely.

Unfortunately, MDS engines have totally different lifters so removing the system requires opening the engine. On my 2011 Challenger I have MDS permanently deactivated via tune. This seems to work well. On my Ram I do what you do and turn it off by entering ERS mode every time I drive.

Thanks for the info. I was on the fence about MDS, always questioned the gas savings (?) vs the mechanical detriments (?). And believe it is more about EPA MPG stats than actual gas savings. Explanation has merits. The effects of MDS (mpg and mechanical detriment) may depend on your driving habits, i.e. highway vs city, heavy foot vs moderate.

 

[WXman]

Thanks for the info. I was on the fence about MDS, always questioned the gas savings (?) vs the mechanical detriments (?). And believe it is more about EPA MPG stats than actual gas savings. Explanation has merits. The effects of MDS (mpg and mechanical detriment) may depend on your driving habits, i.e. highway vs city, heavy foot vs moderate.

Yeah we have to remember that the automaker's desire and the consumer's desire are different. They are selling hundreds of thousands of Hemi engines annually, so every fraction of a mile per gallon adds up to lots of $$$ to them in terms of meeting CAFE scores during EPA testing. That's why they do things like specifying watery 0W20 engine "oil" and using MDS systems. But for the consumer who wants a long lasting engine, 5W30 full synthetic oil and no MDS system is best. Just depends on which seat you're viewing the game from.

 

[jives]

What's the process to turn this off? I'm not sure I've noticed an "ERS mode"

 

[WXman]

What's the process to turn this off? I'm not sure I've noticed an "ERS mode"

The minus and plus buttons on the steering wheel activate ERS. A discussion on this is in the owners manual I think.

 

[mikeru82]

What's the process to turn this off? I'm not sure I've noticed an "ERS mode"

Basically, after shifting to D, press the - button, then press the + button until the gear indicator on the gauge cluster displays 8. Then drive as normal. This allows your transmission to use all 8 gears normally, but MDS will not turn on. Or you can wait until you are up to speed and in 8th gear, then press the - button. Just remember that you'll need to do this every time you shift into D from any other gear selection.

 

[Idahoktm]

The minus and plus buttons on the steering wheel activate ERS. A discussion on this is in the owners manual I think.

Yep, it's in the owners manual. I activate ERS as soon as I drive away from my house by tapping the - button, then tapping the + button until it displays 8th gear in the instrument cluster.

 

[Bt10]

Yep, it's in the owners manual. I activate ERS as soon as I drive away from my house by tapping the - button, then tapping the + button until it displays 8th gear in the instrument cluster.

View attachment 144019

Why would you hit the plus button? Minus changes from D to 8, hitting plus changes from 8 to D.

 

[Idahoktm]

Why would you hit the plus button? Minus changes from D to 8, hitting plus changes from 8 to D.

If you hit the minus button when you aren't in 8th gear, it will select the current gear as the top gear available. If you wait until you are in 8th gear to hit the minus button, there will be no need to hit the plus button.