Molybdenum, Cam wear and Hemi tick

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I asked at my local dealer about this issue, as I saw a lifter on the Service counter and it reminded me of this thread.

From my mechanic buddy's mouth:
- They see about one or two lifter failures a year on the 5.7L engines
- They have never seen one on the 6.4L

The failure I observed on the lifter on the counter was the same as what was discussed in this thread with the roller seizing, skating on the cam lobe and being worn flat.
 
Originally Posted By: OVERKILL
I asked at my local dealer about this issue, as I saw a lifter on the Service counter and it reminded me of this thread.

From my mechanic buddy's mouth:
- They see about one or two lifter failures a year on the 5.7L engines
- They have never seen one on the 6.4L

The failure I observed on the lifter on the counter was the same as what was discussed in this thread with the roller seizing, skating on the cam lobe and being worn flat.
Is the actual camshaft the same on both?
 
So, the valvetrains are the essentially the same. They have failures on the 5.7, but not on the 6.4. The main difference seems to be the oil.
Now, all we need are the internal Fiat Chrysler America documents. I smell a rat
smile.gif
 
This is what I think. Can't prove. The 5.7 only went in the light duty pickups, and lower performance cars. All of which are the volume sellers, therefore crucial to meet CAFE. The 6.4 only goes in the 2500/3500 and hi-po cars, which either don't have to meet CAFE(2500/3500) or are such low volume sellers(hi-po cars), they don't figure into CAFE significantly. To eke out more credits, they spec 5W-20 for the volume 5.7, and the 6.4 gets what it really needs, oil wise.
 
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Originally Posted By: Shannow
Originally Posted By: bigj_16
Is the actual camshaft the same on both?


https://www.moparamerica.com/oem-parts/mopar-camshaft-5038419ab


I know it shows 5.7L, but the entire list of applications are 6.4L SRT engines:



I think we'll find there are serveral different camshafts:

1. 53022372AA - 5.7L camshaft w/MDS for LX cars, Most Durango and Grand Cherokee
2. 53022263AF - 5.7L camshaft w/MDS for RAM 1500 and 2009/2010 Durango/Aspen
3. 5038419AB - 6.4L camshaft w/MDS for SRT vehicles
4. 53022314AD - 5.7L ???MDS for 2500/3500 trucks
5. 5045517AC - 6.4L ???MDS for 2500/3500 trucks


Which, really, is to be expected given the different applications and the different performance levels.

Otherwise however, the valvetrains are essentially identical, and if anything, I would expect a more aggressive cam to be slightly harder on the MDS lifters. Which brings up back to the oil as already mentioned
wink.gif
 
Originally Posted By: bigj_16
This is what I think. Can't prove. The 5.7 only went in the light duty pickups, and lower performance cars. All of which are the volume sellers, therefore crucial to meet CAFE. The 6.4 only goes in the 2500/3500 and hi-po cars, which either don't have to meet CAFE(2500/3500) or are such low volume sellers(hi-po cars), they don't figure into CAFE significantly. To eke out more credits, they spec 5W-20 for the volume 5.7, and the 6.4 gets what it really needs, oil wise.


What are the oil requirements for a 6.4 vs a 5.7?

I know the 5.7 specs a 5w20 and the 6.4 is I think a 0w40? I've read the 5.7 needs 5w20 because of the displacement management system. Is this true?

I've been running Pennzoil Platinum 5w30 in my dad's 2013 GC with the 5.7L and it has been fine with 100k miles on it. I thought a 0w40 might be too steep of a jump.
 
Originally Posted By: jeepman3071
Originally Posted By: bigj_16
This is what I think. Can't prove. The 5.7 only went in the light duty pickups, and lower performance cars. All of which are the volume sellers, therefore crucial to meet CAFE. The 6.4 only goes in the 2500/3500 and hi-po cars, which either don't have to meet CAFE(2500/3500) or are such low volume sellers(hi-po cars), they don't figure into CAFE significantly. To eke out more credits, they spec 5W-20 for the volume 5.7, and the 6.4 gets what it really needs, oil wise.


What are the oil requirements for a 6.4 vs a 5.7?

I know the 5.7 specs a 5w20 and the 6.4 is I think a 0w40? I've read the 5.7 needs 5w20 because of the displacement management system. Is this true?


I've been running Pennzoil Platinum 5w30 in my dad's 2013 GC with the 5.7L and it has been fine with 100k miles on it. I thought a 0w40 might be too steep of a jump.
I know this discussion
smile.gif
is going on two threads. Here is the page with Chrysler recommended oil
https://bobistheoilguy.com/forums/ubbthreads.php/topics/4513864/9

Looks like you can technically run 5W-30 instead of 20 in the 5.7. If he's been running the 30 for 100k, no issues, sounds like a good compromise.
 
Originally Posted By: jeepman3071
Originally Posted By: bigj_16
This is what I think. Can't prove. The 5.7 only went in the light duty pickups, and lower performance cars. All of which are the volume sellers, therefore crucial to meet CAFE. The 6.4 only goes in the 2500/3500 and hi-po cars, which either don't have to meet CAFE(2500/3500) or are such low volume sellers(hi-po cars), they don't figure into CAFE significantly. To eke out more credits, they spec 5W-20 for the volume 5.7, and the 6.4 gets what it really needs, oil wise.


What are the oil requirements for a 6.4 vs a 5.7?

I know the 5.7 specs a 5w20 and the 6.4 is I think a 0w40? I've read the 5.7 needs 5w20 because of the displacement management system. Is this true?

I've been running Pennzoil Platinum 5w30 in my dad's 2013 GC with the 5.7L and it has been fine with 100k miles on it. I thought a 0w40 might be too steep of a jump.


It doesn't "NEED" it, as the components for the system to function are identical between the two engines, despite the massive grade difference. The software programming is however different to allow for the heavier oil and it is possible, although unlikely from what I've seen posted, to trigger a viscosity out of range CEL if you use a 0w-40 in the 5w-20 spec applications.
 
Like SonofJoe I am not a mechanic, and have not done any deep engine work in over 40 years. I also do not know the Redline formulations, but having sold them lots of polyol esters back when I was working I don't doubt their statement that their oils are rich in POEs, blended with PAO. And I know nothing about Hemis, but I was a synthetic oil formulator and do know a bit about esters, so I will try to shine a little light on POEs.

The most common POE used in motor oils is TMP C8C10 which has the following properties compared to PAOs:

Property............TMP C8C10.....PAO 4.....PAO 6
KV @ 100, cSt............4.35.........4.1........5.8
KV @ 40, cSt..............19...........19.........31
KV @ -40, cSt...........5,600.......2,900.....7,800
Viscosity Index..........140..........126........138
Pour Point, °F...........-65...........-87........-71
Flash Point, °F..........490...........428........475
Noack, wt%................3............13.........6.4
Density, g/ml..........0.943........0.820......0.827

Polyol esters can be thought of as PAOs with some oxygen in the molecular chain. Both are pure synthetic compounds consisting mostly of branched hydrocarbons, but the esters have multiple "ester groups" inserted, each containing two oxygens. These ester groups make the molecules polar, i.e. attracted to each other, which accounts for the dramatically higher flash points, lower Noacks, and higher density for a given viscosity. The polarity also imparts lubricity due to metal attraction, and better solvency. The solvency not only helps with solubilizing additives and allowing higher doses, but also dissolves and/or disperses breakdown products, thus reducing deposits at high temperatures. The combination of high and low temperature stability with cleanliness at high temperatures is why POEs are used exclusively in all jet engines worldwide. Even a small addition of PAO would cause the jet turbine oils to fail a specification.

While POEs are essential for jet engines, they tend to be overkill for car engines, and expensive. Some properties that do benefit car engines, however, are high lubricity, high solvency, and low volatility, which is why some synthetic oils continue to use them for PCMOs in spite of the cost. As SonofJoe has theorized, the high doses of POEs in Redline oils could in theory unstick lifters and improve lubrication, but whether this is a factor in the Hemi ticking is unknown. It would take a lot of very expensive testing to prove a correlation and it appears the problem is not frequent enough to justify the expense. If you have a ticking problem, however, an OCI of Redline is a fairly cheap way to see if it works for you.

Tom NJ

PS - Do not use jet engine oils in your car engine!
 
Originally Posted By: OVERKILL
Originally Posted By: jeepman3071
Originally Posted By: bigj_16
This is what I think. Can't prove. The 5.7 only went in the light duty pickups, and lower performance cars. All of which are the volume sellers, therefore crucial to meet CAFE. The 6.4 only goes in the 2500/3500 and hi-po cars, which either don't have to meet CAFE(2500/3500) or are such low volume sellers(hi-po cars), they don't figure into CAFE significantly. To eke out more credits, they spec 5W-20 for the volume 5.7, and the 6.4 gets what it really needs, oil wise.


What are the oil requirements for a 6.4 vs a 5.7?

I know the 5.7 specs a 5w20 and the 6.4 is I think a 0w40? I've read the 5.7 needs 5w20 because of the displacement management system. Is this true?

I've been running Pennzoil Platinum 5w30 in my dad's 2013 GC with the 5.7L and it has been fine with 100k miles on it. I thought a 0w40 might be too steep of a jump.


It doesn't "NEED" it, as the components for the system to function are identical between the two engines, despite the massive grade difference. The software programming is however different to allow for the heavier oil and it is possible, although unlikely from what I've seen posted, to trigger a viscosity out of range CEL if you use a 0w-40 in the 5w-20 spec applications.
Not what I meant by need. Just using it in a very general sense
smile.gif
 
Originally Posted By: bigj_16
Originally Posted By: OVERKILL
Originally Posted By: jeepman3071
Originally Posted By: bigj_16
This is what I think. Can't prove. The 5.7 only went in the light duty pickups, and lower performance cars. All of which are the volume sellers, therefore crucial to meet CAFE. The 6.4 only goes in the 2500/3500 and hi-po cars, which either don't have to meet CAFE(2500/3500) or are such low volume sellers(hi-po cars), they don't figure into CAFE significantly. To eke out more credits, they spec 5W-20 for the volume 5.7, and the 6.4 gets what it really needs, oil wise.


What are the oil requirements for a 6.4 vs a 5.7?

I know the 5.7 specs a 5w20 and the 6.4 is I think a 0w40? I've read the 5.7 needs 5w20 because of the displacement management system. Is this true?

I've been running Pennzoil Platinum 5w30 in my dad's 2013 GC with the 5.7L and it has been fine with 100k miles on it. I thought a 0w40 might be too steep of a jump.


It doesn't "NEED" it, as the components for the system to function are identical between the two engines, despite the massive grade difference. The software programming is however different to allow for the heavier oil and it is possible, although unlikely from what I've seen posted, to trigger a viscosity out of range CEL if you use a 0w-40 in the 5w-20 spec applications.
Not what I meant by need. Just using it in a very general sense
smile.gif



That was directed at jeepman3071, not you bud
smile.gif
 
Originally Posted By: Tom NJ
Like SonofJoe I am not a mechanic, and have not done any deep engine work in over 40 years. I also do not know the Redline formulations, but having sold them lots of polyol esters back when I was working I don't doubt their statement that their oils are rich in POEs, blended with PAO. And I know nothing about Hemis, but I was a synthetic oil formulator and do know a bit about esters, so I will try to shine a little light on POEs.

The most common POE used in motor oils is TMP C8C10 which has the following properties compared to PAOs:

Property............TMP C8C10.....PAO 4.....PAO 6
KV @ 100, cSt............4.35.........4.1........5.8
KV @ 40, cSt..............19...........19.........31
KV @ -40, cSt...........5,600.......2,900.....7,800
Viscosity Index..........140..........126........138
Pour Point, °F...........-65...........-87........-71
Flash Point, °F..........490...........428........475
Noack, wt%................3............13.........6.4
Density, g/ml..........0.943........0.820......0.827

Polyol esters can be thought of as PAOs with some oxygen in the molecular chain. Both are pure synthetic compounds consisting mostly of branched hydrocarbons, but the esters have multiple "ester groups" inserted, each containing two oxygens. These ester groups make the molecules polar, i.e. attracted to each other, which accounts for the dramatically higher flash points, lower Noacks, and higher density for a given viscosity. The polarity also imparts lubricity due to metal attraction, and better solvency. The solvency not only helps with solubilizing additives and allowing higher doses, but also dissolves and/or disperses breakdown products, thus reducing deposits at high temperatures. The combination of high and low temperature stability with cleanliness at high temperatures is why POEs are used exclusively in all jet engines worldwide. Even a small addition of PAO would cause the jet turbine oils to fail a specification.

While POEs are essential for jet engines, they tend to be overkill for car engines, and expensive. Some properties that do benefit car engines, however, are high lubricity, high solvency, and low volatility, which is why some synthetic oils continue to use them for PCMOs in spite of the cost. As SonofJoe has theorized, the high doses of POEs in Redline oils could in theory unstick lifters and improve lubrication, but whether this is a factor in the Hemi ticking is unknown. It would take a lot of very expensive testing to prove a correlation and it appears the problem is not frequent enough to justify the expense. If you have a ticking problem, however, an OCI of Redline is a fairly cheap way to see if it works for you.

Tom NJ

PS - Do not use jet engine oils in your car engine!



Tom,

A couple of questions if I may...

Why are POEs so expensive? My recollection (from VERY long ago!) is that they cost more than PAOs. If TMPC8C10 is the way to go, isn't everything ultimately derived from crude (as opposed to natural fatty acids) so should be cheap-ish? Also, although I'm a pretty rubbish chemist, isn't a simple esterification reaction super easy (and cheap) as compared to say decene polymerisation (for PAO), multi-step hydrocracking/paraffin isomerisation (for Group III's) or Fischer-Tropsch synthesis (for GTL)? I only ask the question because if Esters cost, say somewhere between Group III and PAO, I could easily imagine a route to getting them to be more mainstream.

I'm almost embarrassed to ask this (I'm supposed to be a Chemical Engineer!) but for a given viscosity grade and a given engine, do very dense Ester based oils give you higher oil pressure than say a low density Group II? If no-one's ever checked, it might be a worthwhile experiment.

I know PAO based oils usually contain 5 - 10% Ester to stop elastomer seals drying out but I'm now of the opinion that POE's are sort of wasted in this role. Has anyone seriously considered using POE in cheap Group II 5W30s as a simple Noack trim or as a counter to the very poor solvency of these oils. With the OEMs so fixated on LSPI and 0W8/0W16 this wouldn't be easy but I would have thought some kind of test development to demo the benefits might bear fruit.
 
Hi SoJ,

POEs are expensive because the raw materials (acids and alcohols) are expensive, constituting >80% of the manufactured cost. In the case of C8C10 acid, this is derived from coconut and palm kernel oils. It used to be a by-product and the cheapest acid, but market pressures from other applications, and on the other components of coconut and palm kernel oils, have driven the price way up, like 3X from my days 10 years ago. As a result some have reduced or dropped esters from their formulations or are in the process of changing to different ester structures.

Even the cheaper (saturated) POEs, however, are still more expensive than PAOs last I looked. Yes the processing is simpler, but the volumes are also much smaller than hydrocarbons, and esters are made in small batches rather than in a continuous high volume process like the hydrocarbons.

Regarding the relationship between oil pressure and density, I would have to punt to an automotive engineer or physicist. I designed and formulated many POEs but am not an expert in the physical/mechanical side of applications.

Motor oil formulators have used esters for many years for additive solubility, seal compatibility, and to a lessor extent lubricity and Noack enhancement, but they cry about the price in this highly competitive market. PAO formulations pretty much require a polar component for these reasons, but most Group IIIs and IIs are considered acceptable without esters, or with a tiny dose. Mobil 1 used to use some 15+% POE, but the last time I looked at it 10 years ago they had virtually eliminated the POE and switched to ANs for the polar component. Castrol also used esters in their first version of Syntec in the 1990s before switching to Group III.

Also there is no read-across for esters, so if you want to use any you need to find an approved DI package containing esters or pay dearly for a set of engine tests.

Hatco developed the first API approved synthetic motor oils in 1972 using a 100% diester base and they worked fine. I discontinued the automotive line in the late 80s because the low sales did not justify the cost of re-certification against new specifications. In applications where their benefits are needed, such as jet turbine engines, some refrigeration systems, and high temperature industrial, price is less of an issue. Motor oil, however, is a real doggy market.

Tom NJ
 
Tom,

Thanks for your prompt and honest answers.

I stand corrected on the C8/C10 fatty acids. I knew C16, C18 & C22 fatty acids are all natural extracted fatty acids but thought by now the lower MW ones would be synthesised (I read you could do this by oxidising paraffins). Clearly this isn't the case.

Given what you say about the rapidly rising cost of POEs, I'm not surprised that they've been engineered out of their traditional role in PAO top-tier. I spent several years formulating at the brutal end of the crankcase market. I think I shocked people when I first joined BITOG and said that my top three formulation priorities weren't engine wear, oil robustness and cold-startability but rather cost, cost and cost!

Since leaving the engine oil formulation business, I've undergone something of a Damascene conversion regarding what makes a good oil. I've totally lost faith in the bodies which control oil quality. All of the major players are working the system to further their own short-term objectives with ZERO regard for the general motoring public who ultimately pick up the tab for everything. I think there's definitely a business opportunity for someone to start formulating oils to meet long-term, real-life conditions rather than suites of engine & rig tests which are not only eye-wateringly expensive but are increasingly divorced from any recognisable automotive reality. I could imagine that POEs might would shine in this environment.
 
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I agree with your priority on cost for such competitive markets. We know how to make a better oil but it's a waste of time if it won't sell. Some 20 years ago I formulated a military jet engine oil, which is still used in most military jets to this day. Having won and lost multi-million dollar bids by as little as a penny a quart, I set my three highest priorities as cost, cost, and cost. Naturally it had to meet the grueling specifications set forth by the military, but if I wanted to sell it the cost had to come down. As it turns out we made a superior oil for about 15% lower cost, and won every bid thereafter. Sometimes it works out that way.

The problems with making superior motor oils are the competitive market, the high cost of certification, the lack of demand, and the inability to prove it is superior with the standard API engine tests designed for mineral oils. A few years ago a friend and I set out to formulate the best performing motor oil we could without regard for cost or certification. It contained three special esters totaling over 50% and the balance of the base oil state was a 5 cSt PAO (C12 olefin). We used it in our engines and got fine UOAs, but that proves nothing and it would have had to sell for $15/quart. Fortunately we did it just for fun and did not invest any money in it.

With the current trend for low viscosity oils with high VI, high lubricity, and low volatility, POEs are ideally suited from a technical standpoint. Still I believe the oils will continue with Group III and GTLs with some PAO as needed for low temperature flow, rather than take advantage of POEs due to cost.

Tom NJ
 
Quote:
Has anyone seriously considered using POE in cheap Group II 5W30s as a simple Noack trim or as a counter to the very poor solvency of these oils

Isn't this fundamentally what products like Castrol Magnatec are ?

Sure it's started out as a Group II & Group III semi-synthetic with Esters as the "intelligent" polar molecule. I believe the formula has evolved into a Group III full-syn with AN. But same basic idea.

BTW 10+ year ago, the Castrol Magnatec data sheets clearly stated in writing that Magnatec contained Esters, and the reason was to attach themselves to the metal surface of the engine. The modern data sheets tell very little in comparison.
 
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