For the guys who think deactivating the mds via a tune is a good idea

[Docwagon1776]

It's not the brand, it is the dealer

It's not either/or as both play their own role. Just like some McDonald's are better than McDonald's but none are going to be a Ruth Chris in levels of service or attention. Corporate culture, including how dealerships are rewarded, vary.

 

[HEMIMANN]

What are your thoughts on long term wear characteristics for another metal part in the engine? (billet yokes)

Can't make blanket statements for all parts. Each part should be designed to meet the functionality, reliability, and durability targets set for the product. I worked in engineering, marketing, sales, and product line management, co-authored many product and technical profiles back in the day.

For wear alone, the first rule is to use dissimilar materials to reduce galling. Typically one part needs to be harder than the other for the same reason.
Example - piston rings coated with chromium are very hard and wear resistant. Grey cast iron or coated aluminum cylinder walls are still very hard and wear resistant, but not nearly as much as chromium.
Combined with good lubrication and filtration, this is why engine power cylinders last so long. The science is well known today.

 

[Black1500Ram]

Can't make blanket statements for all parts. Each part should be designed to meet the functionality, reliability, and durability targets set for the product. I worked in engineering, marketing, sales, and product line management, co-authored many product and technical profiles back in the day.

For wear alone, the first rule is to use dissimilar materials to reduce galling. Typically one part needs to be harder than the other for the same reason.
Example - piston rings coated with chromium are very hard and wear resistant. Grey cast iron or coated aluminum cylinder walls are still very hard and wear resistant, but not nearly as much as chromium.
Combined with good lubrication and filtration, this is why engine power cylinders last so long. The science is well known today.

Sorry should have been more specific, I was referring to having billet metal lifter yokes long term

 

[HEMIMANN]

Sorry should have been more specific, I was referring to having billet metal lifter yokes long term

Ok, I have not worked on that machine element, but I will say that plastic lifter yokes visually appeared to be a higher quality plastic in terms of resistance to wear, heat, and vibration.

It appears to be polyphenylene sulfide, or PPS, as it's known. I do not KNOW if that is what it is, but PPS has a unique appearance and that's what these looked like when I got them out.

As plastics go, that's one of the better choices
But I can't comment on how many engine revolutions they will last for, because it doesn't have a cyclic load fatigue failure limit. Only testing could tell.

We used PPS on Naval Missile Launcher contactor modules for high loads (slams into missile potted contactor), wide temp range stability. But - missile launches are way, way less than an engine lifter actuation over the life of the engine.

Since consumers don't know, short of high hour experiences, we change to billet when we 1st go into the cam chest.

 

[ramsare4real]

Well this is embarrassing, I always thought it was fine as I see it all over the forum that guys use +/- gear selector to kill MDS. I do it all the time too.

My poor lifters. Thanks for the info!

I didn't get the memo...

 

[markabby]

8 PSI makes more sense, I'm not sure why 16 jumped into my head and out of my keyboard.

.

i just read the normal oil pressure for a 5.7 hemi is 25 to 65 psi.

this was interesting:

Is MDS Damaging Your HEMI? The Answer May Surprise You!

I feel like MDS has been unfairly made the culprit for the lifter failures we see on Gen 3 Hemi engines. In this video I explain exactly how the system works...

www.youtube.com

 

[Wild one]

i just read the normal oil pressure for a 5.7 hemi is 25 to 65 psi.

this was interesting:

Is MDS Damaging Your HEMI? The Answer May Surprise You!

I feel like MDS has been unfairly made the culprit for the lifter failures we see on Gen 3 Hemi engines. In this video I explain exactly how the system works...

www.youtube.com

RD was referring to the pressure in the lifter galleries when the solenoids are closed.The oil pressure does drop in the galleries,when oil flow to the lifters is restricted by the solenoids

 

[Bmags]

I didn't get the memo...

It is fine to use that... These people all complaining about MDS shutting down the oil pressure to their lifters and causing issues don't make any sense when you listen to their argument.

When the truck is running, there is plenty of oil pressure (not to mention oil splashing) to sufficiently coat all moving parts in oil whether MDS is on or off.

At idle however there is never MDS activation (whether enabled or disabled)... and the low idle speed of ~550RPM also happens to have the lowest oil pressure your vehicle will see. So the real culprit to lifter/cam failure is excessive idling. I'd be way more interested in hearing how many of the people that have lifter issues will admit to idling their trucks often for prolonged periods of time. Heck it's even tracked, we can just grab the screen shots of it from the EVIC

If you want to help your hemi, keep the oil level full and don't idle your truck for long periods of time... or add in a custom tune to bump up the idle if you want. But billet cams and blah blah blah aren't the fix, you are just replacing the part that wears out without addressing the real problem.

 

[Wild one]

But billet cams and blah blah blah aren't the fix, you are just replacing the part that wears out without addressing the real problem.

Not much the average guy can do to address the root cause of the cam/lifter issue,so they're best defense is to replace the cam with a good quality aftermarket cam,and totally delete the mds system,if they do have cam issues.
Till then,the best defense is to probably leave the mds system working,at least then the lifters get the odd high pressure oil flow to the bores,and hopefully a little more leakage past the lifter bores to help lubricate the lobe and roller.
If you have an easy mechanical fix to the issue,you'll be a rich man,if you develop it,and start selling it.

 

[ramffml]

It is fine to use that... These people all complaining about MDS shutting down the oil pressure to their lifters and causing issues don't make any sense when you listen to their argument.

When the truck is running, there is plenty of oil pressure (not to mention oil splashing) to sufficiently coat all moving parts in oil whether MDS is on or off.

At idle however there is never MDS activation (whether enabled or disabled)... and the low idle speed of ~550RPM also happens to have the lowest oil pressure your vehicle will see. So the real culprit to lifter/cam failure is excessive idling. I'd be way more interested in hearing how many of the people that have lifter issues will admit to idling their trucks often for prolonged periods of time. Heck it's even tracked, we can just grab the screen shots of it from the EVIC

If you want to help your hemi, keep the oil level full and don't idle your truck for long periods of time... or add in a custom tune to bump up the idle if you want. But billet cams and blah blah blah aren't the fix, you are just replacing the part that wears out without addressing the real problem.

It's not idling related IMHO. Too many cases of engines at high miles and high idling and 0 lifter issues. We also have enough of cases of lifter failure with low idle hours.

The lifter failures need engine runtime to happen (right, it's a wear item and it needs to run to wear). So when enough run time occurs, either by driving or idling, a poorly hardened cam or poorly manufactured lifter will destroy itself regardless of RPM level. If its running, it'll wear. But it's not strictly related to idling. In other words if you have the junk cam/lifter it will eat itself when either enough idling or driving occurs, but if you don't idle it you'll still get the failure just with more drive hours instead.

Here is a great example: 603,000 KM (375,000 miles), 3700 idle hours no failures at this point:

Reddit - Dive into anything

www.reddit.com

Example #2 would be "truck central" on YT, about 250,000 miles with hard towing and 1600+ idle hours, dealer oil 5w-20, no failures yet.

There are many other examples, I just don't remember them all.

 

[RainZeros]

I'm hoping somebody who has made it over a 100,000 miles with MDS deleted via a tune,and hasn't had a lifter failure,will post.
Im curious if anybody has turned it off via a tune at say 60 or 70,000 miles and then made it to 160,000+ miles with it just defeated via a tune

Well, I'm getting there for sure. I bought this truck at 50k, started defeating it with the +/- at 55k, physically unplugged the solenoids at 68k along with tuning it out, I'm now sitting at 110k and the only tick I have is my stupid exhaust manifold that's got 2 visibly broken bolts. (Next months project) 55k miles with no mds and my lifters are fine. Hell I've blown the "indestructible 8 speed transmission" before I had a lifter problem.

I use 5w30 pup and do an oil change every 4000 miles. Oil comes out looking great every single time.

I suppose I'll post an update in here if I get lifter tick or something but I really don't see it happening. I'm firmly in the camp of "if tow/haul mode disables mds on 5th gens, and pressing a button on the steering wheel disables mds, and idling it's firing on all 8 cylinders, then clearly it's designed to run on all 8" imagine providing a feature (any method of mds defeat) that causes excessive wear from lack of oil flow, it makes no sense. Imagine the amount of warranty work stelantis could prevent if it were true that disabling mds causes excessive wear.

Edit: that all said, I used to believe that mds was the cause of the cam/lifter problems, I firmly don't believe that anymore. If you are defeating mds because of worrying about your cam and lifters, i'd recommend against it. I just really really dislike the concept of buying an 8 cylinder for it to be a 4 cylinder 30-50% of the time otherwise I never would have unplugged my solenoids.

 

[Black1500Ram]

It's not idling related IMHO. Too many cases of engines at high miles and high idling and 0 lifter issues. We also have enough of cases of lifter failure with low idle hours.

The lifter failures need engine runtime to happen (right, it's a wear item and it needs to run to wear). So when enough run time occurs, either by driving or idling, a poorly hardened cam or poorly manufactured lifter will destroy itself regardless of RPM level. If its running, it'll wear. But it's not strictly related to idling. In other words if you have the junk cam/lifter it will eat itself when either enough idling or driving occurs, but if you don't idle it you'll still get the failure just with more drive hours instead.

Here is a great example: 603,000 KM (375,000 miles), 3700 idle hours no failures at this point:

Reddit - Dive into anything

www.reddit.com

Example #2 would be "truck central" on YT, about 250,000 miles with hard towing and 1600+ idle hours, dealer oil 5w-20, no failures yet.

There are many other examples, I just don't remember them all.

or me I’m the exact opppsite I have 700 idle hours, <15% of total, and I had to replace the cam.

everything I’ve seen in my mildly educated opinion has pointed to metallurgy not lubrication.

 

[Wild one]

Well, I'm getting there for sure. I bought this truck at 50k, started defeating it with the +/- at 55k, physically unplugged the solenoids at 68k along with tuning it out, I'm now sitting at 110k and the only tick I have is my stupid exhaust manifold that's got 2 visibly broken bolts. (Next months project) 55k miles with no mds and my lifters are fine. Hell I've blown the "indestructible 8 speed transmission" before I had a lifter problem.

I use 5w30 pup and do an oil change every 4000 miles. Oil comes out looking great every single time.

I suppose I'll post an update in here if I get lifter tick or something but I really don't see it happening. I'm firmly in the camp of "if tow/haul mode disables mds on 5th gens, and pressing a button on the steering wheel disables mds, and idling it's firing on all 8 cylinders, then clearly it's designed to run on all 8" imagine providing a feature (any method of mds defeat) that causes excessive wear from lack of oil flow, it makes no sense. Imagine the amount of warranty work stelantis could prevent if it were true that disabling mds causes excessive wear.

Keep us updated,as i'm curious on that scenerio myself. My truck is deleted and has been since it was virtually new,as i put the delete plugs in,when i did the hi-po cam close to 9 years ago,while both my 300 and 1320 still have mds activated,so i'm curious on how defeating it just by a tune holds up in the long run.

 

[Wild one]

or me I’m the exact opppsite I have 700 idle hours, <15% of total, and I had to replace the cam.

everything I’ve seen in my mildly educated opinion has pointed to metallurgy not lubrication.

I agree,i think it's poor quality / cheap cam cores,and not enough surface hardening,all done to save a few bucks per vehicle

 

[RainZeros]

Keep us updated,as i'm curious on that scenerio myself. My truck is deleted and has been since it was virtually new,as i put the delete plugs in,when i did the hi-po cam close to 9 years ago,while both my 300 and 1320 still have mds activated,so i'm curious on how defeating it just by a tune holds up in the long run.

Will do. My ram is now exclusively my "reliable daily" so I don't see myself doing the whole cam mds delete anytime soon. I have a whole jeep MJ to rebuild before I bother with more upgrades to the ram... But then again I do have this addiction to buying parts and breaking my only means of transportation... I was out of both trucks for a couple months with them both being in the middle of projects!

 

[RainZeros]

Now that I'm home I figured I'd take a look at my engine hours on my truck that "should have lifter failure" I'm at 862 idle hours, 2814 driving hours for a total of 3676 hours, still tick free, still not plugging those damn solenoids back in. Side note, it's a 2017. Didn't they improve the roller bearings for 2017 on?

 

[JHoward]

"I bought this truck at 50k, started defeating it with the +/- at 55k, physically unplugged the solenoids at 68k along with tuning it out, I'm now sitting at 110k ..."

I'm curious about the "tuning it out" part. I guess "unplugging the solenoids" would be the same as just pulling them out altogether and replacing them with the block off plugs?

 

[JHoward]

Now that I'm home I figured I'd take a look at my engine hours on my truck that "should have lifter failure" I'm at 862 idle hours, 2814 driving hours for a total of 3676 hours, still tick free, still not plugging those damn solenoids back in. Side note, it's a 2017. Didn't they improve the roller bearings for 2017 on?

Yep, larger bearings cam ~2017.

 

[RainZeros]

I'm curious about the "tuning it out" part. I guess "unplugging the solenoids" would be the same as just pulling them out altogether and replacing them with the block off plugs?

I always hated mds, but I just couldn't justify a tune for a while. Anyways as typical with all these hemis, the pcv had sent so much oil into my intake and I decided to pull my manifold, clean it and regasket it. I read somewhere on here that installing the plugs without a non-mds cam would cause problems, but leaving them in and unplugged would be fine. So while I was cleaning my intake manifold on my truck I said screw it and unplugged em.

That gave me a cel because of course it would. It convinced me to finally get an unlocked ECU and a tuner. I have mds disabled in my tune and I've never had any problems.

Is it totally possible that I misread something and could have just put in the block off plugs? Of course it is. Do I care enough to pull my intake manifold off again to replace the solenoids with block off plugs? No way haha.

Besides, it's like an egr delete, if it's unplugged, it's effectively blocked off the same as a plate would do.

 

[JHoward]

I always hated mds, but I just couldn't justify a tune for a while. Anyways as typical with all these hemis, the pcv had sent so much oil into my intake and I decided to pull my manifold, clean it and regasket it. I read somewhere on here that installing the plugs without a non-mds cam would cause problems, but leaving them in and unplugged would be fine. So while I was cleaning my intake manifold on my truck I said screw it and unplugged em.

That gave me a cel because of course it would. It convinced me to finally get an unlocked ECU and a tuner. I have mds disabled in my tune and I've never had any problems.

Is it totally possible that I misread something and could have just put in the block off plugs? Of course it is. Do I care enough to pull my intake manifold off again to replace the solenoids with block off plugs? No way haha.

Besides, it's like an egr delete, if it's unplugged, it's effectively blocked off the same as a plate would do.

Interesting. You left the MDS lifters in, did a tune to keep the CEL from coming on and unplugged the solenoids ... and a lot of miles/idle hours, etc. and no "ticky".

My 5.7 HEMI is also year model 2017. The mileage is currently @50, 000 miles with slightly higher than the norm engine hours ... It doesn't have the "ticky", but that may be that I don't baby it and kick it in the ass alot. Idk.