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Harmonic isolators missing on 22 PW?

CI6

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Wondering if all 22 PWs came without the harmonic isolators. On both sides, the wiring is there but caps have been put instead of the isolator.

This is the part


In the process of installing rock sliders and noticed them missing. Is this from the chip shortage? does the PW have the MDS turned off? My understanding is that they are supposed to dampen when the MDS is activated.
 
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CI6

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figured out the right name

it is called an ATMM Actuator

here is the part number 68363377AB


Seems like i did not get all of my 2022 PW parts installed, maybe the chip shortage resulted in no MDS and therefore no need for this.

Only had the ECO light up show up a couple of times, but not convinced that means MDS being activated.
 

jadmt

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I have read several reports of this so my guess is it has to do with the chip shortage and must not be needed as people say they can not feel any undue vibrations. when your eco light comes on hit the +/- button (hit the minus) on your steering wheel and see if you can perceive and difference. try and be on a smooth road going like 40 mph or so. music off fan off or low etc.
 

CI6

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will try and see if there is a difference, would be estatic if MDS is not present
 

jadmt

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will try and see if there is a difference, would be estatic if MDS is not p
Even with the isolators, you can still feel MDS kick in. I'm also not entirely sure the isolators are there solely for MDS.
that is my understanding too. I thought it had something to do with the stiffer frame as well. If no one actually notices they are gone I might pull mine, cut down on weight lol. probably throw a code and put me in limp mode and void my warranty.....
 

CI6

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Can’t tell a difference when eco light goes on, no difference when hitting the -, doing this in the city so may not be hearing the difference but no noticeable change in the feeling of engine vibrations via the steering wheel

Crossing my fingers no MDS
 
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jadmt

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if you are feeling it in the steering wheel you have mds, I would be extremely surprised if it was left off simply because of the atmm's being left off.
 

CI6

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Oops typo, meant to say No noticeable

I’ll edit my post
 

jetrinka

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I've never felt MDS through the steering wheel at all. Its always been a certain frequency felt through the truck itself as well as an audible exhaust noise difference. That being said its also always been very light - almost not noticeable. I hear it much more now with the aftermarket muffler I have put on but it still doesn't bother me.

I promise you the truck has MDS. They've just gotten good at masking the feeling/sound of it in stock form.
 

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In one of the articles that introduced ATMM on the 1500 it called out that ATMM would only work when MDS is active. I can't find anything that states the same for the HDs, but can't see why it would be tuned any different.
 

CI6

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Is there any other way of telling if mds is activated

I can not feel or hear a difference when eco light turns on, and when I use the - gear shift also no difference

Without the ATMM presume it would be easier to feel it come on, if MDS is actually a feature on my MY22 PW
 

jetrinka

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Your truck likely had a build sheet. It’ll say MDS in the engine description on it
 

CI6

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Yes and by vin I’m supposed to have two ATMMs and can confirm they were not installled on the truck

So maybe RAM owes me parts, those are not cheap
 

jetrinka

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Well if you get a mirror in so you can see under the intake you should see 4 MDS solenoids. It doesn’t mean they are activated but the engine would have been built with it. I suppose just like the diesels the new Hemis could have come without certain things installed/enabled with a recall in mind. We heard about that with the diesels though not the Hemi
 

JamesEvan

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Wondering if all 22 PWs came without the harmonic isolators. On both sides, the wiring is there but caps have been put instead of the isolator.

This is the part


In the process of installing rock sliders and noticed them missing. Is this from the chip shortage? does the PW have the MDS turned off? My understanding is that they are supposed to dampen when the MDS is activated.
Found out mine were missing on my 22 PW when we installed my carli kit, confirmed with the RAM they weren't on my build. Don't really notice MDS kicking in so not sure they would have made much of a difference.
 

Chris85xlt

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i could feel the MDS on the Ram 1500 but nothing on the 22' PW. i thought maybe Ram got really good at masking the MDS

Edit: I just looked underneath and also missing the two ATMMs
 
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Hibiki54

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Found out mine were missing on my 22 PW when we installed my carli kit, confirmed with the RAM they weren't on my build. Don't really notice MDS kicking in so not sure they would have made much of a difference.
So what did Ram do when they said they were not on your build?
 

JamesEvan

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So what did Ram do when they said they were not on your build?
Nothing, just said it wasn't part of my build nor could they find a part # for it. So either supply chain issues, they aren't including them in our model moving forward or both. If you want to notice MDS just remove your mid-muffler like I did :D
 

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