Disable MDS

[SpookyWatcher]

I think someone else already touched on it here. But be careful of continually running without mds enabled. From my understanding the main oil galley to the mds lifters is controlled by the mds solenoids. It servers two purposes...solenoid on, it will oil the lifter AND deactivate the mds lifter so it can "float" and deactivate the cylinder. With mds off...your not getting ANY oil from the main side body mds lifter galley. Now probably at rpm of 1500 or more this might not be a problem. But it certainly seems like a big boo boo on the part of the engineers imho.

So it might be that the only real solution is MDS delete. Pull the mds solenoids and replace with the plugs. And of course replace the mds lifters and reprogram. Then you would have full oil going to those lifters like the others full time.

For me...after seeing how the mds lifter gets deactivated by the oil galley that's controlled by the mds solenoid, I want that system engaging as much as possible so they get oiled as much as possible being that the lifters were raised AND tilted to a more flat state.

But again..this is just my understanding of how the mds lifters work and get oiled. I could be completely wrong. But as always...Hope it helps.

SpookyWatcher

 

[silver billet]

I think someone else already touched on it here. But be careful of continually running without mds enabled. From my understanding the main oil galley to the mds lifters is controlled by the mds solenoids. It servers two purposes...solenoid on, it will oil the lifter AND deactivate the mds lifter so it can "float" and deactivate the cylinder. With mds off...your not getting ANY oil from the main side body mds lifter galley. Now probably at rpm of 1500 or more this might not be a problem. But it certainly seems like a big boo boo on the part of the engineers imho.

So it might be that the only real solution is MDS delete. Pull the mds solenoids and replace with the plugs. And of course replace the mds lifters and reprogram. Then you would have full oil going to those lifters like the others full time.

For me...after seeing how the mds lifter gets deactivated by the oil galley that's controlled by the mds solenoid, I want that system engaging as much as possible so they get oiled as much as possible being that the lifters were raised AND tilted to a more flat state.

But again..this is just my understanding of how the mds lifters work and get oiled. I could be completely wrong. But as always...Hope it helps.

SpookyWatcher

I posted this in another similar thread yesterday, but there are 2 problems with that theory; when you tow a trailer, MDS is disabled, so I don't believe FCA would design an engine that does not lubricate itself properly when worked the hardest, nor would they give us the ability to turn off MDS ourselves if it would wreck the engine (just think of all the transmission safetys etc). Secondly, non MDS lifters are also seizing, which means even with the constant oil there it doesn't do anything one way or the other. Most likely cause (IMHO) is improper oil maintenance with dirty oil seizing the needle bearings, or just a bad lifter (poor quality control from the vendor etc).

 

[SpookyWatcher]

No doubt You are correct that the needle bearings are the failure point. And dirty oil and low rpm idle causing insufficient oil getting to the needle bearings most likely are the causes of the needle bearings failing. Coupled with the lifter being raised and flattened out angle wise, I personally, also believe (for now) that mds turned off could also be a provocateur of the failures.

I agree with You... under "normal" circumstances turning off mds with tow/haul mode or +/- shouldn't be cause for concern. But I truly believe that turning off mds 100% of the time will cause the condition to accelerate the failures.

The latest iteration of the lifters (I believe part ending in "E") have substantially bigger needle bearings and may have solved the issue including non mds lifters failing, but for me and mine.... I'll be letting mds do it's thing + changing oil every 5k or 8 months whichever comes first and not idling for long periods. But that's just me... And I only hope to spread info (hopefully info that is correct) for others to increase knowledge and make their own decision. Again... to all who might come across this. This is just my opinion. I'm not any kind of mechanic. Just some dude playing a dude disguised as another dude.



Cheers!

SpookyWatcher

 

[CMil527]

Get in start er up and hit the gear selector to 8.. done!

 

[silver billet]

No doubt You are correct that the needle bearings are the failure point. And dirty oil and low rpm idle causing insufficient oil getting to the needle bearings most likely are the causes of the needle bearings failing. Coupled with the lifter being raised and flattened out angle wise, I personally, also believe (for now) that mds turned off could also be a provocateur of the failures.

I agree with You... under "normal" circumstances turning off mds with tow/haul mode or +/- shouldn't be cause for concern. But I truly believe that turning off mds 100% of the time will cause the condition to accelerate the failures.

The latest iteration of the lifters (I believe part ending in "E") have substantially bigger needle bearings and may have solved the issue including non mds lifters failing, but for me and mine.... I'll be letting mds do it's thing + changing oil every 5k or 8 months whichever comes first and not idling for long periods. But that's just me... And I only hope to spread info (hopefully info that is correct) for others to increase knowledge and make their own decision. Again... to all who might come across this. This is just my opinion. I'm not any kind of mechanic. Just some dude playing a dude disguised as another dude.

View attachment 88090

Cheers!

SpookyWatcher

I'm just a dude with an opinion too so.... but I think the fact that FCA modified the MDS lifters (needle bearings) speaks volumes. I also think if the lifters were starved of oil then a 3 hour continuous trip with MDS disabled (for a 3.21 on the freeway, that's about 1400 rpms sustained in my case), well they would be dead at the end of the trip. Oil starvation tends to blow things out very quickly (minutes and hours), I don't see how the engine can run for 130,000+ miles with improper lubrication. Some lifters go after < 20K, some after 150K, that doesn't look like oil starvation to me.

I really wish Uncle Tony would take down his videos because they're causing a lot of damage; all it is is speculation at this point but for some reason his theory has grown legs.

 

[SpookyWatcher]

Ah..the good ole Uncle Tony offense. Well for your edification and peace of mind, I'm not referencing or using any of his info from his videos. I'm using this guy's video

where he shows how the mds lifter (AND actually it's neighbor cylinder non mds lifters) are NOT getting oil from the main side body lifter oil galley when when the solenoid is off. It physically blocks the oil from even reaching the lifter side body bore oil galley. Let that sink in! ALL Lifters are NOT getting PRESSURIZED oil to the lifter bores from the galley when MDS is OFF. Again...let that sink in. Only when MDS is activated does pressurized oil populate the lifter bore oil galleys and reach the lifter bores.

According to the guy in the vid he seems to be under the impression of mds lifters failing at a much higher rate go to the 11:12 mark in the vid. But maybe we shouldn't take a tech of FCA engines for 20yrs into account. I'm sure you have much better stats on lifter failure rate. But hey... You keep doing You! I believe both sets are failing because both are not getting oil to their bores when MDS is off.

Cheers!

ETA: The mds solenoid controls oil going to the lifter bores and hence the lifters of BOTH PAIR of cylinders eg cylinders 1 & 3 then 5 & 7 etc etc. One being an mds cylinder and one being regular cylinder. This is very important. Because if the solenoid is deactivated (mds OFF) the Two cylinders' lifters are NOT receiving oil to the lifter bores. Both the mds lifters and solid lifters of the cylinder next to the mds cylinder ARE NOT gettting pressurized oil to their lifter bores. This is the reason why BOTH types of lifters are failing. Even non mds lifters. Because they are not getting oil to their bores unless the mds is activated.

So I'll be leaving mds on. I'm hoping my lifters are of the "E" part number variety being a sept '20 build. And as mentioned earlier... Oil change every 5k or 8 months and no idling. And if even after that I get lifter failure. I'll do the mds delete. The mds delete will cause the lifter bore galleys to be pressurized with oil 100% of the time.

 

[mikeru82]

Sorry, can't watch videos from work. I've been turning off MDS since I bought my first truck with a Hemi equipped with it (2017 Rebel). Owned that truck for 3 years with no issues, and have had my current truck for 18 months with no issues. You'd think if there is an oiling issue with the lifters when MDS is off, and I've almost always disabled it, I should have seen a problem by now. I can't speak to what is in the video. And anyone making a video can claim whatever credentials they want. I just find it hard to believe that anyone would have designed an engine that provides insufficient oil during some of the most strenuous times for an engine, like when towing. No one is trying to convince anyone not to use MDS. So why try to convince anyone to keep it active?

 

[jdefoe0424]

I believe that there has to be a small bleed hole in the mds solenoid to allow some amount of oil through. Otherwise the lifter bore could almost always be dry and things would end very quickly.
I'm more inclined to think it's a matter of cheap oil, improper maintenance and low oil pressure with long periods of hot idle.

Sent from my Moto Z (2) using Tapatalk

 

[silver billet]

Ah..the good ole Uncle Tony offense. Well for your edification and peace of mind, I'm not referencing or using any of his info from his videos. I'm using this guy's video

where he shows how the mds lifter (AND actually it's neighbor cylinder non mds lifters) are NOT getting oil from the main side body lifter oil galley when when the solenoid is off. It physically blocks the oil from even reaching the lifter side body bore oil galley. Let that sink in! ALL Lifters are NOT getting PRESSURIZED oil to the lifter bores from the galley when MDS is OFF. Again...let that sink in. Only when MDS is activated does pressurized oil populate the lifter bore oil galleys and reach the lifter bores.

According to the guy in the vid he seems to be under the impression of mds lifters failing at a much higher rate go to the 11:12 mark in the vid. But maybe we shouldn't take a tech of FCA engines for 20yrs into account. I'm sure you have much better stats on lifter failure rate. But hey... You keep doing You! I believe both sets are failing because both are not getting oil to their bores when MDS is off.

Cheers!

ETA: The mds solenoid controls oil going to the lifter bores and hence the lifters of BOTH PAIR of cylinders eg cylinders 1 & 3 then 5 & 7 etc etc. One being an mds cylinder and one being regular cylinder. This is very important. Because if the solenoid is deactivated (mds OFF) the Two cylinders' lifters are NOT receiving oil to the lifter bores. Both the mds lifters and solid lifters of the cylinder next to the mds cylinder ARE NOT gettting pressurized oil to their lifter bores. This is the reason why BOTH types of lifters are failing. Even non mds lifters. Because they are not getting oil to their bores unless the mds is activated.

So I'll be leaving mds on. I'm hoping my lifters are of the "E" part number variety being a sept '20 build. And as mentioned earlier... Oil change every 5k or 8 months and no idling. And if even after that I get lifter failure. I'll do the mds delete. The mds delete will cause the lifter bore galleys to be pressurized with oil 100% of the time.

I've watched that video several times; we've been arguing this over in the other forum last month too.

There is no rhyme or reason to which lifter is failing. This guy happens to see twice as many MDS, but then throws in other stats like differences in where the truck is running (which state) etc, which is completely bonkers in my opinion. He also sees more 6.4's (which is unlikely since the 5.7 is sold everywhere from jeep to durango to challenger to charger to 1500 etc etc, there are far more 5.7's built than 6.4's). So I do have issues with projecting his personal stats onto the entire population of hemis.

And actually, an MDS delete removes pressurized oil 100% of the time; so if you do that, according to your theory you will make the problem worse. His whole point is that instead of just doing an MDS delete, you would need to MDS delete AND find a way to turn on MDS mode 100% of the time (which no tuner can do yet).

So again, in point form:
- FCA sells (factory item) block off plates to disable this
- aftermarket companies remove MDS lifters completely and that MDS oil galley is never used anymore.
- both types of lifters are failing, but yet there is a difference in failure rate even though both get oiled/not oiled at the same time
- fca has addressed this problem by modifying the MDS lifter; they claimed "poor quality control at a vendor" for these lifter errors. That's their official response to this problem.
- fca gives us the ability to turn off MDS whenever we want; they've known about this problem since 2009? 2010? And yet 10 years later with a simple software tweak they could "fix" the problem by preventing us from turning off MDS, but they don't.
- MDS is disabled anyway as soon as a load is attached; either using TH, or simply because the load is too heavy for 4 cylinder mode. If lifters were not getting adequate lubrication, trucks would not be able to go 200,000 miles without failure while being worked hard each and every day.

So while I do appreciate this guy's breakdown on how MDS works, his presentation and reasoning etc., I don't believe his final conclusion is correct.

 

[Neurobit]

I've watched that video several times; we've been arguing this over in the other forum last month too.

There is no rhyme or reason to which lifter is failing. This guy happens to see twice as many MDS, but then throws in other stats like differences in where the truck is running (which state) etc, which is completely bonkers in my opinion. He also sees more 6.4's (which is unlikely since the 5.7 is sold everywhere from jeep to durango to challenger to charger to 1500 etc etc, there are far more 5.7's built than 6.4's). So I do have issues with projecting his personal stats onto the entire population of hemis.

And actually, an MDS delete removes pressurized oil 100% of the time; so if you do that, according to your theory you will make the problem worse. His whole point is that instead of just doing an MDS delete, you would need to MDS delete AND find a way to turn on MDS mode 100% of the time (which no tuner can do yet).

So again, in point form:
- FCA sells (factory item) block off plates to disable this
- aftermarket companies remove MDS lifters completely and that MDS oil galley is never used anymore.
- both types of lifters are failing, but yet there is a difference in failure rate even though both get oiled/not oiled at the same time
- fca has addressed this problem by modifying the MDS lifter; they claimed "poor quality control at a vendor" for these lifter errors. That's their official response to this problem.
- fca gives us the ability to turn off MDS whenever we want; they've known about this problem since 2009? 2010? And yet 10 years later with a simple software tweak they could "fix" the problem by preventing us from turning off MDS, but they don't.
- MDS is disabled anyway as soon as a load is attached; either using TH, or simply because the load is too heavy for 4 cylinder mode. If lifters were not getting adequate lubrication, trucks would not be able to go 200,000 miles without failure while being worked hard each and every day.

So while I do appreciate this guy's breakdown on how MDS works, his presentation and reasoning etc., I don't believe his final conclusion is correct.

Agree 100% with this assessment.

 

[SpookyWatcher]

And actually, an MDS delete removes pressurized oil 100% of the time; so if you do that, according to your theory you will make the problem worse. His whole point is that instead of just doing an MDS delete, you would need to MDS delete AND find a way to turn on MDS mode 100% of the time (which no tuner can do yet).

Once again... You prove that you are 100% completely wrong and don't fully understand what you are talking about.

First off, the guy in the vid even corrects himself down in the comments somewhere. Stating that with the block off plates installed there is pressurized oil reaching the lifter bore galleys 100% of the time.

Look at the vid at time stamps 19:30 and compare to time stamp 21:45. The solenoid (functioning part that actually does the blocking off of pressurized oil) is way down in the block. The block off plate is very shallow and only just "caps" the block it does NOT block the galley.

Obviously You think You are the expert and big dog here and have seem to have convinced many others that the facts I presented are untrue. But You are 100% wrong. Full Stop. And you are so blinded by your own hubris that you take the facts that contradict your stance (and those that present them) as an afront to your manhood and continue to argue falsehoods.

It's plain and simple. The solenoid part that actually does the moving and blocking of oil is DOWN in the block (timestamp 19:30). Take that away and put the blocking plate in...and that just "caps" the block and plugs the top hole (timestamp 21:45). But Oil is now flowing 100% of the time to the lifter bores.

But I can't keep arguing with dense foam. I obviously won't change Your opinion as well as others. So go ahead and get the last word if you feel the need. Just make sure it's factually correct. And I hope that others who are smart enough to see facts as they are make their own informed decision.

SMH... "I can't believe the engineers would be so stupid as to make a square window in a pressurized aircraft." "Cracks around the windows causing explosive decompression couldn't possibly be why it went down!"

 

[silver billet]

Once again... You prove that you are 100% completely wrong and don't fully understand what you are talking about.

First off, the guy in the vid even corrects himself down in the comments somewhere. Stating that with the block off plates installed there is pressurized oil reaching the lifter bore galleys 100% of the time.

Look at the vid at time stamps 19:30 and compare to time stamp 21:45. The solenoid (functioning part that actually does the blocking off of pressurized oil) is way down in the block. The block off plate is very shallow and only just "caps" the block it does NOT block the galley.

Obviously You think You are the expert and big dog here and have seem to have convinced many others that the facts I presented are untrue. But You are 100% wrong. Full Stop. And you are so blinded by your own hubris that you take the facts that contradict your stance (and those that present them) as an afront to your manhood and continue to argue falsehoods.

It's plain and simple. The solenoid part that actually does the moving and blocking of oil is DOWN in the block (timestamp 19:30). Take that away and put the blocking plate in...and that just "caps" the block and plugs the top hole (timestamp 21:45). But Oil is now flowing 100% of the time to the lifter bores.

But I can't keep arguing with dense foam. I obviously won't change Your opinion as well as others. So go ahead and get the last word if you feel the need. Just make sure it's factually correct. And I hope that others who are smart enough to see facts as they are make their own informed decision.

SMH... "I can't believe the engineers would be so stupid as to make a square window in a pressurized aircraft." "Cracks around the windows causing explosive decompression couldn't possibly be why it went down!"

He is claiming MDS lifters fail at twice the rate. If there was a lack of lubrication, that wouldn't be the case. The more likely case (very likely considering the response from FCA themselves, not some random tech) is that they had quality control issues with their lifter. This is supported by the fact that many engines never develop lifter issues, and yet run with MDS off their entire life. Some lifters go at 50,000 miles with MDS active, and others run to end of life without problems all while MDS is never active.

You think a work truck can go 200,000 miles with improper lubrication?
How many consecutive hours do you think a truck can pull a 7000 pound load on the freeway for, without having the lifter destroy itself due to oil starvation? I'm up to 4 hours so far (have to stop for gas again).

Lets go one more step down the rabbit hole, this is one of his comments:
"My own personal opinion is that unless you are in the habit of idling your vehicle for excessive periods of time, say 1hr+ each day, then you'll likely be just fine even with the MDS turned off during towing."

So now we're getting into lifter failures, "while idling". And this is probably the second problem. Not lack of lack of lubrication, but lots of cars that are idling (cop cars) and not doing proper oil change intervals. Extensive idling requires oil to be changed every 320 hours, I'm sure they all do that like clockwork right? Every 2 to 4 weeks? Not likely. GM's v8's also have similar lifter failures, they also use the same needle bearings for the lifters. Dirty oil is going be a big problem in these engines.

Judging by the tone of your last response I must have shot your dog in a previous life or something

May you have many problem free miles on your hemi; I hope to as well (with MDS disabled of course.)

 

[CMil527]

Lol yeah seriously I get we have a forum of alpha's here but geez everything seems to turn into a shiet show once people disagree.. suddenly manhood is questioned yada yada... relax guys I thought the point here was discussion and sharing thoughts and opinions?

 

[Lufty]

Lol yeah seriously I get we have a forum of alpha's here but geez everything seems to turn into a shiet show once people disagree.. suddenly manhood is questioned yada yada... relax guys I thought the point here was discussion and sharing thoughts and opinions?

Just use the ignore button. It works great...

 

[HemiDude]

After you do it for a while it becomes second nature. If you let it get up to 8th gear on it's own you only need to press gear down once

Unless you live on my street. My truck reaches 4th gear as I approach a long decline to a stop sign and let off the gas. Before I had MDS disabled, 8/10 times it would kick in at that point.

 

[Scram1500]

Unless you live on my street. My truck reaches 4th gear as I approach a long decline to a stop sign and let off the gas. Before I had MDS disabled, 8/10 times it would kick in at that point.

Yeah that's a pain, having it come on when the engine isn't at operating temperature can't be good