HEMI 5.7 engine autopsy findings from a 2011 Dodge Challenger

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This is an interesting quote regarding OEM recommended oil.

The link to the full article is attached at the end of the thread.

"Do a web search for "Hemi camshaft failures," and you'll find a few thousand photos of gouged cam lobes, most of them the result of lifter failures on MDS cylinders. Because this author's wife dutifully changed the full synthetic 5W30 oil every 5,000 miles over the Hemi's 235,000-mile life (that's about $4,000 worth of oil changes!), this bumpstick looks pristine for such a high-mileage unit. This one passes inspection and can go for another 100K miles. Folks, on an MDS-equipped Hemi, it's vitally important to use the right oil and viscosity at the right change intervals. Not doing so risks contaminating the oil and blocking the lube circuit into or out of one of the MDS lifters, causing it to not lock or unlock the plunger. Higher viscosities than 5W30 also cause the plunger in the MDS lifter to delay the locking action until the lobe's clearance ramp has ended and the lifter is on its way up, eliminating the important cushion provided by the plunger's hydraulic lash."

I think I'll stick with PUP 5w20...

Article here https://www.motortrend.com/how-to/hemi-engine-problems-2011-dodge-challenger/
 
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This is an interesting quote regarding OEM recommended oil.

The link to the full article is attached at the end of the thread.

"Do a web search for "Hemi camshaft failures," and you'll find a few thousand photos of gouged cam lobes, most of them the result of lifter failures on MDS cylinders. Because this author's wife dutifully changed the full synthetic 5W30 oil every 5,000 miles over the Hemi's 235,000-mile life (that's about $4,000 worth of oil changes!), this bumpstick looks pristine for such a high-mileage unit. This one passes inspection and can go for another 100K miles. Folks, on an MDS-equipped Hemi, it's vitally important to use the right oil and viscosity at the right change intervals. Not doing so risks contaminating the oil and blocking the lube circuit into or out of one of the MDS lifters, causing it to not lock or unlock the plunger. Higher viscosities than 5W30 also cause the plunger in the MDS lifter to delay the locking action until the lobe's clearance ramp has ended and the lifter is on its way up, eliminating the important cushion provided by the plunger's hydraulic lash."

I think I'll stick with PUP 5w20...

Article here https://www.motortrend.com/how-to/hemi-engine-problems-2011-dodge-challenger/
How can the viscosity make the difference, when some of the 6.4's specifying 0w-40, and the 5.7 specifying a lower viscosity, use the same lifters?
 

wwillson

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Folks, on an MDS-equipped Hemi, it's vitally important to use the right oil and viscosity at the right change intervals. Not doing so risks contaminating the oil and blocking the lube circuit into or out of one of the MDS lifters, causing it to not lock or unlock the plunger.
I wonder how many of these lifter failures occurred with the correct spec oil? Probably most I would imagine. So most have the correct spec oil and have clogged lube circuits in the lifters. That sounds like the correct spec oils needs more ability to resist oxidation, better dispersants, and detergents. This could be a fine example of "meets spec" just isn't good enough.
 
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digitalcassidy

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I wonder how many of these lifter failures occurred with the correct spec oil? Probably most I would imagine. So most have the correct spec oil and have clogged lube circuits in the lifters. That sounds like the correct spec oils need more ability to resist oxidation, better dispersants, and detergents. This could be a fine example of "meets spec" just isn't good enough.
Good point!
 
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I have read many accounts of failures in engines that were idled a lot. I have a camping buddy that had a failure at a bit over 100k, and he used to let it idle while he ate lunch. I'm not sure the lifters get good oiling at idle , at least the older versions.

@OVERKILL iirc says there have been many lifter revisions over the years.
 
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How can the viscosity make the difference, when some of the 6.4's specifying 0w-40, and the 5.7 specifying a lower viscosity, use the same lifters?

Are they also using the same cam? Wouldn't a different lift profile and height give different contact pressures during operation? Do both engines also have the same redline? Do both engines also have the same in cylinder pressures at valve opening? Do both engines also have the same transmissions and ratios resulting in similar operating RPM's? What about cooling and operating temps?
 

OVERKILL

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This is an interesting quote regarding OEM recommended oil.

The link to the full article is attached at the end of the thread.

"Do a web search for "Hemi camshaft failures," and you'll find a few thousand photos of gouged cam lobes, most of them the result of lifter failures on MDS cylinders.
Nope, they aren't mostly on the MDS cylinders, there's a pretty good split between the MDS cylinders and non-MDS cylinders.
Because this author's wife dutifully changed the full synthetic 5W30 oil every 5,000 miles over the Hemi's 235,000-mile life (that's about $4,000 worth of oil changes!), this bumpstick looks pristine for such a high-mileage unit. This one passes inspection and can go for another 100K miles. Folks, on an MDS-equipped Hemi, it's vitally important to use the right oil and viscosity at the right change intervals.
That's amusing, that car spec's 5w-20:
Screen Shot 2022-05-18 at 3.39.21 PM.jpg

Not doing so risks contaminating the oil and blocking the lube circuit into or out of one of the MDS lifters, causing it to not lock or unlock the plunger.
The locking of the plunger is from the REMOVAL of oil pressure. Ergo, "blocking" of the circuit wouldn't have any impact on locking.
Higher viscosities than 5W30 also cause the plunger in the MDS lifter to delay the locking action until the lobe's clearance ramp has ended and the lifter is on its way up, eliminating the important cushion provided by the plunger's hydraulic lash."
Nope. 0w-40 is spec'd for the SRT engines (and the 6.4L truck engine) which have the exact same lifters and MDS components. The lock for the plunger can only re-engage when the lobe is on the base circle and the plunger is all the way at the top. There's no way for it to lock when the lifter is on its way up, the plunger would already be passed the lock.
 

OVERKILL

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I have read many accounts of failures in engines that were idled a lot. I have a camping buddy that had a failure at a bit over 100k, and he used to let it idle while he ate lunch. I'm not sure the lifters get good oiling at idle , at least the older versions.

@OVERKILL iirc says there have been many lifter revisions over the years.
Well, an engine doesn't get miles on it right, it gets hours. We use miles as a proxy for hours but idle hours aren't included in miles-based OCI's.

Our fleet of 2011/2012's all idle lots. All are over 200,000 miles now and only one had a lifter failure. These trucks have not received "premium" service. Their lives have been on NAPA (Valvoline) bulk 5w-20 and NAPA filters.

And yes, there have been MANY lifter revisions over the years, I posted a list recently.

The lifters are oiled just like any other pushrod engine, that is, through the body of the lifter. What is somewhat unique is that half the lifters are fed from the body-up (bores are pressurized, oil goes in the lifter, up the pushrod), the other half (the MDS lifters) are fed from the top down, which comes down the pushrod, into the body and out into the bore. This is done because oil pressure on the lifter body is used to activate the MDS system.
 

OVERKILL

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Are they also using the same cam? Wouldn't a different lift profile and height give different contact pressures during operation? Do both engines also have the same redline? Do both engines also have the same in cylinder pressures at valve opening? Do both engines also have the same transmissions and ratios resulting in similar operating RPM's? What about cooling and operating temps?
None of that has any impact on the MDS system, which only engages/disengages on base circle.
 

ZeeOSix

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Not so sure these guys tearing down the engine know what they are talking about. Carbon doesn't build up on cylinder heads from a coolant leak. A coolant leak will actually clean carbon off the combustion chambers. If one cylinder head has more carbon build up than the other, first thing to look at is how the PCV works, and which cylinders will be drawing in more crankcase vapors.

From the article:

Signs Of Thermal Stress
010 left right hemi cylinder head comparison


As Wadlund tore down the Hemi, we carefully noted the normal and the abnormal wear. Our first hint that this was a distressed engine was in comparing the passenger-side cylinder head combustion chambers (left) with the driver-side combustion chambers. While the driver's side looks normal or even excellent for a high-mileage engine with 235K miles, the passenger-side is rife with carbon and other deposits (possibly coolant residue). These deposits are not consistent with cylinders controlled by MDS, leading us to believe the MDS was not involved; we suspect a head gasket failure.
 
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I have read many accounts of failures in engines that were idled a lot. I have a camping buddy that had a failure at a bit over 100k, and he used to let it idle while he ate lunch. I'm not sure the lifters get good oiling at idle , at least the older versions.

@OVERKILL iirc says there have been many lifter revisions over the years.

I had to stop at a parking lot last night to make a phone call, I shut my car off and I was talking with someone for 20 minutes. A few spaces over this guy is sitting there with his car running, and when I leave a few minutes after my phone call he is still sitting there with the car idling.

Unless I am wrong, there is probably more oil flow at 1500 to 2000 rpms versus like 500 rpms at idle.
 
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I thought the camshaft failures were due to a rather large bad batch of lifters? Like they would seize or turn and then the sideways roller would chew up the cam?
 

OVERKILL

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I thought the camshaft failures were due to a rather large bad batch of lifters? Like they would seize or turn and then the sideways roller would chew up the cam?
Yes, both GM and FCA had the issue with improper hardening on lifter components that would lead to failure. FCA (now Stellantis) had many, MANY revisions of the lifters. Basically, according to @TeamZero the pin that the needles for the roller roll on isn't properly hardened and, eventually, if it is defective, will start to wear, creating a divet/ditch in which the needles catch. Eventually, the ditch gets large enough to stop the needles from rolling and then the needles pile up, stopping the roller in its tracks. At this point, with the roller no longer rolling on the lobe, it doesn't take long before both it, and the lobe, are destroyed.

There's also been some separate issues of lobe pitting on some cores.
 
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I think I'll stick with PUP 5w20...
Thank you for posting this. My father has my 2016 RAM 1500 now. I used to run Mobil 1 FS 0W-40 and Red Line 5W-30 in it. It keeps the engine clean, but that was about it. The best modifications that I did to it I believe are the following:

  1. When I flushed the coolant I also replaced the thermostat with a 180F Mishimoto thermostat.
  2. I did a grille shutter delete by removing eight out of twelve louvers.
  3. I always used a big oil filter. The brand doesn't matter so much, though I recommend against Royal Purple filters because they tend to have dirt and rust in them.
  4. I swapped the air cleaner housing with the one from the 3.0 EcoDiesel engine. The engine can breathe easier now, and it's a relatively cheap mod.
  5. After I did the mods above I found that the engine runs best on 0W/5W-20. So now it's running Mobil 1 EP 5W-20.
Coolant temps rarely exceed 185F, and the oil barely reaches 200F on hot summer days now. The HEMI runs very happy on this combination of mods. Oil gets changed every 5K to 7K miles and it looks great when it comes out. Under the valve covers the engine looks great. Sticking with PUP 5W-20 is also a good choice. Bringing down the engine temperature is more important than the brand of oil you use in it.
 
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Yes, both GM and FCA had the issue with improper hardening on lifter components that would lead to failure. FCA (now Stellantis) had many, MANY revisions of the lifters. Basically, according to @TeamZero the pin that the needles for the roller roll on isn't properly hardened and, eventually, if it is defective, will start to wear, creating a divet/ditch in which the needles catch. Eventually, the ditch gets large enough to stop the needles from rolling and then the needles pile up, stopping the roller in its tracks. At this point, with the roller no longer rolling on the lobe, it doesn't take long before both it, and the lobe, are destroyed.

There's also been some separate issues of lobe pitting on some cores.
So what you're saying is, it is a metalurgy issue and no oil will help it.
 
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