Why still no MDS Disable 3rd party device?

[Buz]

I can feel the truck bog, then kick off every time.

Exactly. That's the best way I've heard it described to date. The truck 'bogs' when in eco and light throttle is applied. Looses its 'smooth as glass' feeling.

 

[NHjake98]

Exactly. That's the best way I've heard it described to date. The truck 'bogs' when in eco and light throttle is applied. Looses its 'smooth as glass' feeling.

I agree with you Buz. The transition from 8 cylinders to 4 is sloppy at best.

I find myself driving in Tow/Haul mode around town. I don't notice it that much on the highway so I just leave it alone. I do notice that it does delay the throttle response until the truck warms up.

 

[Grape_Ape]

I'd be interested in a way to permanently disable MDS. I understand it's a function of our trucks for gas savings but I'd prefer to leave it using 8 cylinders at all times. I worry about the additional wear on the other 4 cylinders. May be misplaced worry but it's something I think about.

I have the E torque and when it does kick into MDS I can't even tell most of the time. Sometimes I can tell from a different exhaust tone. I was also against the auto start/stop but after watching one of the engineering videos on it with the etorque I decided to leave it on most of the time unless it's really frequent stop and go traffic.

 

[SD Rebel]

I'd be interested in a way to permanently disable MDS. I understand it's a function of our trucks for gas savings but I'd prefer to leave it using 8 cylinders at all times. I worry about the additional wear on the other 4 cylinders. May be misplaced worry but it's something I think about.

I have the E torque and when it does kick into MDS I can't even tell most of the time. Sometimes I can tell from a different exhaust tone. I was also against the auto start/stop but after watching one of the engineering videos on it with the etorque I decided to leave it on most of the time unless it's really frequent stop and go traffic.

I think the same way, though the non-working cylinders are still moving up and down, they just aren't being fed fuel. In the scheme of things, I think wear between non and active cylinders is probably very small over the lifetime. However, there is so much going on to make this work, I rather just not do it since the fuel savings is so small.

Though the actual known issues of Hemi motors, the MDS related issues is not common.

 

[HSKR R/T]

I'd be interested in a way to permanently disable MDS. I understand it's a function of our trucks for gas savings but I'd prefer to leave it using 8 cylinders at all times. I worry about the additional wear on the other 4 cylinders. May be misplaced worry but it's something I think about.

I have the E torque and when it does kick into MDS I can't even tell most of the time. Sometimes I can tell from a different exhaust tone. I was also against the auto start/stop but after watching one of the engineering videos on it with the etorque I decided to leave it on most of the time unless it's really frequent stop and go traffic.

From my understanding of MDS, it doesn't always disable the same cylinders. It basically cycles through them all. So while there are always four disabled, it's not always the same four cylinders.

 

[Drewster]

From my understanding of MDS, it doesn't always disable the same cylinders. It basically cycles through them all. So while there are always four disabled, it's not always the same four cylinders.

Nope, always 1, 4, 6, and 7.

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.hotrod.com

On the plus side, no one has really torn open an old Hemi and found weird wear. Chrysler at one point stated

"The modern Hemi always shuts off the same four cylinders. In our durability test cycle
(150,000 customer equivalent miles driven at the 95th percentile, meaning
that only 5% of our owners are more abusive than our testing),
we have not found any adverse wear patterns."

https://www.allpar.com/threads/mode...emi-magnum-v8-engines.230003/#post-1085224101

 

[TruckDriver]

I'd be interested in a way to permanently disable MDS.

My good friend (Mopar master mech among other brands) said that's one of the first things he does in motor swaps; if you're under warranty, don't touch it, but afterwards and in his own hellcat swap, he says you have to physically gut the cam system from the motor - I didn't get into details but permanent removal of the system is pretty intensive

 

[Buz]

Pretty sure there’s a device coming soon that just tells the truck to turn it off permanently. Or until you remove the device.

 

[Olive Green 5.7]

Pretty sure there’s a device coming soon that just tells the truck to turn it off permanently. Or until you remove the device.

Proof?

 

[Buz]

Proof?

No proof. Just hope.
Page 1, post #10.

 

[iLikeTurtles]

I believe the tow haul button is proof

 

[NHjake98]

I believe the tow haul button is proof

I read somewhere that the Pulsar will allow you to turn MDS off.

 

[silver billet]

I believe the tow haul button is proof

Yes Ram can definitely do this, the question is, due to the lockout techniques employed, can a third party connect to the truck and disable it.

I believe the Pulsar (or whatever device that claims to do this) does this by fooling the truck, it basically sends a light press of the gas pedal (almost imperceptible) and then lets off again, which prevents MDS from activating because MDS doesn't come on under a load and needs a second or two of no load before coming on.

 

[Drewster]

Yes Ram can definitely do this, the question is, due to the lockout techniques employed, can a third party connect to the truck and disable it.

I believe the Pulsar (or whatever device that claims to do this) does this by fooling the truck, it basically sends a light press of the gas pedal (almost imperceptible) and then lets off again, which prevents MDS from activating because MDS doesn't come on under a load and needs a second or two of no load before coming on.

Nah, if you just slowly ease off the gas, MDS will engage long before you get to 0%. I only know this because I tend to ease off the gas on level road until I get into "eco"

 

[silver billet]

Nah, if you just slowly ease off the gas, MDS will engage long before you get to 0%. I only know this because I tend to ease off the gas on level road until I get into "eco"

The point is, the only device that disables MDS right now, is one that fools the truck by sending out a slight "blip" in the gas pedal. There is no guarantee that just because Ram can disable MDS, that a third party device can connect to the system and disable it properly without a poor hack.

 

[iLikeTurtles]

I think the logic of 'if no one has done it yet therefore it is not looking likely' seems invalid. Be an optimist! It can only get better.

 

[silver billet]

I think the logic of 'if no one has done it yet therefore it is not looking likely' seems invalid. Be an optimist! It can only get better.

It is possible to design a bus such that no third party is getting in (legally or otherwise). The encryption techniques are widely used for decades (it's why, for example, you can do online banking securely).

I like to be a realist. Look at the trajectory, every redesign it gets harder and harder and eventually its game over.

 

[iLikeTurtles]

I presume there are not enough interested parties/money for aftermarket to persue it. If the c8 corvette ECU can get cracked then MDS will find a way to be modified in these for a price I am sure.

 

[silver billet]

I presume there are not enough interested parties/money for aftermarket to persue it. If the c8 corvette ECU can get cracked then MDS will find a way to be modified in these for a price I am sure.

I'm sure demand is a huge part of it, but demand in itself is not always enough. If Ram was determined, they could build a system where you're not getting in, demand or no. The question is, how determined was Ram on our 5th gens

I think John Deere tractors are like this now? I remember talking to my cousin who is a farmer while back, I don't remember whether it was just a legal thing or not, but I'm pretty sure he said they were locked out and nobody could get in. Lawsuits over it and everything, farmers want to repair their stuff but the system in place prevents that.

 

[Drewster]

I presume there are not enough interested parties/money for aftermarket to persue it. If the c8 corvette ECU can get cracked then MDS will find a way to be modified in these for a price I am sure.

The issue is not "cracking" the ECU - it looks like Edge/ Holley will let you swap your PCM when you buy their $500 tuner https://edgeproducts.com/shop/dodge-ram-evoht2-pcm-swap-8-speed-only-589

HP Tuners appears to support MDS disable as well - but you need to buy a dongle ($300), credits ($100), and ship your ECU in for modification ($250)

The issue appears to be that FCA removed the ISO command to command MDS, so you can't make a cheap dongle that sends a command and does what you want - you have to ship the ECU in and tune it. *Then* you have to ask whether you want to disable MDS bad enough to pay $500-$650