CK-4 Diesel Oil for old 6.0l PowerStroke?

I hate to pile on... but Roadrunner1 has done extensive UOA analysis and should be considered someone to be listened to on this one. His long track record convinced me to switch to 10w30 in my own truck back in 2014/2015. My truck was bulletproofed and tuned... often with a hot tune specifically for trucks that had been head studded (hotter tune gets better mileage). I know you and I already chatted in your oil filter thread so I won't keep going, but the 10w30 advise really is the best advise.

If you want to run a 5w40 - that's completely your prerogative obviously. But much like my advise in the other thread was, I'd recommend heeding it here too. Worry about things like effective temp & voltage monitoring, replacing the weak alternator with a stronger one, ensure your FICM is over 48v at all times and replace if lower, flush any silicate coolant if you have it and get some silicate free ELC in there (add a coolant bypass filter while you're at it), upgrade or get rid of the stupid EGR cooler. Then pray your head bolts hold everything together and you don't need to do a head gasket... or if you do - that it doesn't nerf your heads in the process.

Those are the things to worry about - not which grade of oil you use or which oil filter to use. This one really is simple. If you want to use a 5w40 - no problem! It will run fine - please don't overthink it. Heeding the advise from those of us that have had these trucks and spent quite a bit of time (and money) wrenching on them isn't a bad idea either... we can't all be wrong - can we?
 
Originally Posted by sdude2k2000
I hate to pile on... but Roadrunner1 has done extensive UOA analysis and should be considered someone to be listened to on this one. His long track record convinced me to switch to 10w30 in my own truck back in 2014/2015. My truck was bulletproofed and tuned... often with a hot tune specifically for trucks that had been head studded (hotter tune gets better mileage). I know you and I already chatted in your oil filter thread so I won't keep going, but the 10w30 advise really is the best advise.

If you want to run a 5w40 - that's completely your prerogative obviously. But much like my advise in the other thread was, I'd recommend heeding it here too. Worry about things like effective temp & voltage monitoring, replacing the weak alternator with a stronger one, ensure your FICM is over 48v at all times and replace if lower, flush any silicate coolant if you have it and get some silicate free ELC in there (add a coolant bypass filter while you're at it), upgrade or get rid of the stupid EGR cooler. Then pray your head bolts hold everything together and you don't need to do a head gasket... or if you do - that it doesn't nerf your heads in the process.

Those are the things to worry about - not which grade of oil you use or which oil filter to use. This one really is simple. If you want to use a 5w40 - no problem! It will run fine - please don't overthink it. Heeding the advise from those of us that have had these trucks and spent quite a bit of time (and money) wrenching on them isn't a bad idea either... we can't all be wrong - can we?


From some one that works on these every day, i will say he is right, regarding things to be concerned about. This engine has its weaknesses, but oil is not really one of the them. Head gaskets, EGR cooler, and oil cooler are the big three, followed by the FICM, fuel injectors and sticking union ring in the VGT turbo. Good batteries and a healthy are also a must. Being an 04 model, also possible it has the failure prone swash plate style High pressure oil pump.

Good luck with the truck. Tel your son to do some research on the problem areas and learn to fix the Truck himself. Paying someone to do it won't be cheap.

Also just a little education, these injectors suffer from "stiction", but not from "Pintle", as your original concern. The spool valve the solenoids control sticks mechanically. The spool valve directs oil flow to the intensifier piston to fire the injector. The spool valve can stick from debris in the oil, a weak solenoid (open or close solenoid), poor injector supply voltage or injector harness problems.
 
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Not saying anybody's wrong. Asking to assess the new information. Nobody's interested. Oh, well. I expected better from BITOG. I should probably leave again. Told Admin to take down entire post. Been a waste.
 
Really man? Your reaction is like someone standing on a rock wall, getting ready to dive into a lake. You ask a group of experienced people "of these three spots, where should I jump?" And everyone says "none - over here is safer because the water is deeper." And you get upset because nobody answered which of the three spots you chose is better. Of course we can't give you a specific recommendation based on what you're asking - because there's a better solution altogether that's now recommended by most independent diesel shops, and even CAT for their industrial HEUI diesels.

If you want to use a 5w40, use one - that's fine - it's not like it's going to wreck your motor or injectors, it's just going to shear to a 30 weight within a thousand or so miles... that's really all in the short term. Long term could this varnish the injectors? Maybe. At the end of the day, if you want to jump in one of the three spots you've chosen - have at it. We're just trying to give you hands-on guidance. I hope the admin doesn't delete this thread personally, because I'm sure a more open minded 6.0L owner could read it and gain some good hands-on knowledge. Perhaps even say "wow - thanks!". I know I certainly did when I had my 6.0L... I was happy for those who came before me that were willing to give feedback and advise.

Much like your oil filter thread - the answer is simple. 10w30 and an OEM oil filter.
 
All three are proven diesel oils. Seems to me they would all be reasonable candidates. Assuming that he would not experience any significant difference in using either of the three options, I would rule out the most expensive one.

That leaves:
- Valvoline Premium Blue Extreme, available from Amazon, Walmart, O'Reilly's for ~ $29 / gallon.
- Shell Rotella T6, available all over the place around $22 / gallon.

Any discounts, rewards card points, store gift cards or shipping costs in play to consider?

I have not personally used either one, only the conventional mineral oil 15w-40 of these two. Just added the Valvoline to my Benz yesterday, so can't really comment yet on it.

But the Rotella T4 performed well for me, just as advertised. The T6 is the least expensive option, which is a bonus. He may need to add some oil at some point while out on the road. If so, that Rotella T6 is only a Shell gas station, WalMart or auto parts store away.

So putting on my oil consultant hat, if you were my neighbor, based on my own experience with T4, I would point you towards the Rotella T6.
 
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The T6 will be the most shear stable. In fact it is excellent. It is also very good in the volatility department. I have run KRL and TGA and can tell you first hand. I have not measured the difference in wear directly in our lab so I cannot speak to that but from my experience I'd nudge you to the T6. The VI Improver will be at a higher concentration but it does not matter because it is rock solid.

The best advice I can give you if you have a 7.3, 6.0, or 6.4 is to meet Brian at BTS in Lead Hill Arkansas. There is a reason people drive from all over the country to have him work on their trucks. It is the same reason all 9 of my current trucks and 13 in total have made the 500 mile trip to his shop. One of the best in the business hands down.

David
 
Well said!

I have posted data on several 5W40 oil's that show that a 5W40 doesn't always shear quickly. Many (maybe even most) do, but some very common ones do not. I have so much data showing several oils that, after 5k miles, barely drop down to what the 30 weight oils started at. I have a lot of data at 7.5k miles also and several oils are still in the high 30 wt range even after those miles (11.6 to 12.0 cSt). BTW - the 30 wt oils will shear also. Many of them shear from 12 to 10.5 cSt in 5k miles. Fact is I don't believe that ANY 5W40 will shear to a 30 wt in 1k miles.

So many self-proclaimed experts still seem to believe all 5W40's are created equal in the shear category. They aren't. All that said, I still don't understand why people make such a big deal about shear. If starting with a 30 weight is fine (which it is), why not use a 40 weight and drive it longer?

BTS sure sold me a great transmission!
 
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Because shear rate of unstable VII additive negates its lubrication property in high shear rate machine areas (power cylinder wall and piston ring interface, valve cam and lifter, and to a lesser extent, the journal bearings. Under temporary "stretch" shear, the viscosity reduces to the base oil viscosity. The effect is not getting lubrication you paid for with a lab / gravity flow viscosity VII higher viscosity multigrade. You pay for nothing.

But it can be worse than that. UOA shows some VII additives permanently shearing apart, producting labe measured viscosity loss after use. For instance, a 10W-40 virgin oil may shear down to 10W-30 after use. So what? The breakup of VII additive can react / oxidize to form deposits. So not only do you not get the higher vis lubrication you paid for, you can actually damage your engine with it. Especially problematic for HEUI engines that use engine oil as a hydraulic oil actuating the injectors. This instability in the oil can contribute to the infamous injector "stiction" of the HEUI injectors.

I discussed VII additives with a Lube Engineer last night. He confirmed Shell uses a shear stable "star" molecule instead of the typical "coil" molecule that is subject to high shear rate ineffectiveness. Shell advertised it heavily some years back. Retains most of the high vis under high shear rates and doesn't break apart. Not all VII additives are created equal anymore. Don't know if Shell created it or an additive supplier.
 
JV between Mobil and Shell

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Within reasonable OCI's the wear metal data doesn't really show any significant downside to a 40 wt shearing to the mid 30 wt range. I've seen quite a bit of data.
 
Originally Posted by bismic1
Well said!

I have posted data on several 5W40 oil's that show that a 5W40 doesn't always shear quickly. Many (maybe even most) do, but some very common ones do not. I have so much data showing several oils that, after 5k miles, barely drop down to what the 30 weight oils started at. I have a lot of data at 7.5k miles also and several oils are still in the high 30 wt range even after those miles (11.6 to 12.0 cSt). BTW - the 30 wt oils will shear also. Many of them shear from 12 to 10.5 cSt in 5k miles. Fact is I don't believe that ANY 5W40 will shear to a 30 wt in 1k miles.

So many self-proclaimed experts still seem to believe all 5W40's are created equal in the shear category. They aren't. All that said, I still don't understand why people make such a big deal about shear. If starting with a 30 weight is fine (which it is), why not use a 40 weight and drive it longer?

BTS sure sold me a great transmission!


Do you own a 6.0L? Have you worked on or consistently maintained a 6.0L? Are you familiar with how a HEUI diesel works? It forces darn near hydraulic pressures on the oil... and yes - will shear a 40 weight into a 30-weight in no time. Will a 30 weight shear too? Perhaps - but compare the ending viscosity of a 5w40 and a 10w30 after a 5k-7.5k run - and I'd bet dollars to donuts they will be within less than 1cst of each other. Greater shear of a 40 weight runs the risk of issues with the injectors long term (stiction). And since the 6.0L doesn't have any mechanical assist on the injectors - its a real bummer (and not cheap) to have to replace the injectors when it happens. CAT is a large HEUI operator, and they don't give a rip about CAFE requirements (well - at least during the mid-2000s)... they care about keeping their loggers & heavy mech operators in business with minimal downtime and long rebuild life cycles. The primary oil spec us 10w30 for every HEUI they run.

Nobody here is trying to say they're a "self proclaimed oil expert"... Rather most of the advise being given is from actual hands on experience over a long period of time. Either with their own rig, or by maintaining them through a flat or a shop. It's not about trying to argue over whether a 5w40 will work or not, because of course it will work. It's about trying to provide knowledge and education from hands on experience, and back it up with actual facts from other OEM recommendations for the same engine design. If someone insists on running a 40 weight - right on - have at it - it will lubricate your engine fine. So will a 10w30 though. It's not the engine that is of primary concern in this case - it's the injectors. We just don't want people to be naive to the facts - that's all.
 
I own a 6.0l and have 220k trouble free miles on it. I work on them as well. I also own a 7.3L so I understand the HEUI technology and components. My 7.3L has 275k on it and both engines still have the original (HEUI) injectors. Never have experienced stiction, never have had a contribution code.
Unfortunately the 7.3L needed a new HPOP and the 6.0L has needed a new FICM.

My personal experience on 5.0L OCI is limited to 7.5k miles. I agree that 10W30's have been known to go to 10k miles in the 6.0L, but data shows them to be in the lower range of a 30 wt at that point. Some 10W30's were even very close to a 20 wt.

I understand the shear and I am a data hound. Been watching the 6.0L for over 15 years.

I have compared the 10W30 shear on several oils with that of the 5W40 and at 5k miles there is a clear difference of several cSt. I have seen and participated in these discussions on over 12 6.0L forums. These discussions aren't new by any means. I have presented the data more times than can be easily counted.

My perspective is certainly data driven.

10W30 oils can work extremely well in the 6.0L. No question. The 5W40 does shear more than the 10W30 - just by nature of the additives required for the viscosity range. So shearing does occur - just not quite as extreme as what gets stated on many forums. Most 5W40's are at the viscosity that the 30 weight oils start at after 5k miles. The 5W40's with higher quality base oil will not fall to the viscosity of the virgin 10W30 oils until around 7.5k miles. This is true with Schaeffers, Mobil 1 TDT, Mobil Delvac 1, and even Amsoil.
 
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Attached is my analyses that includes data from 10W30 users (some of the data is from roadrunner I believe). This analyses was done years ago.
[Linked Image]
 
The Mobil Delvac 1 data:

Mobil Delvac 1

miles........cSt
7,347.......11.73
7362........12.8
7488........11.74
7,399.......12

I have additional data since doing the analyses above, but it is very much the same as what is posted.
 
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My buddy runs D1 in his 2017 PSD … and in some of his diesel toys. Tipped him off when Walmart had a sale and he ordered 45 gallons. Said it came to him over a one week period in boxes of one, two, three, or four gallons, LoL
 
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