Looking for a synthetic 15w40

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Yes but the 10w30 gives me a noticeable and measurable icp drop. Thsts the injection pressure. I have pretty larger than stock injectors so I notice it more than others. Plus a huge icp pump too
 
Originally Posted By: NattyBoh
Yes but the 10w30 gives me a noticeable and measurable icp drop. Thsts the injection pressure. I have pretty larger than stock injectors so I notice it more than others. Plus a huge icp pump too


You're going to have to explain the connection between your ICP and engine oil viscosity. Are you saying the pump is controlled by engine oil viscosity and a lower one results in lower fuel pressure?
 
The pump takes oil and pressurizes it to 4000psi give or take. My pump actually builds more but the excess is vented off. The thinner the oil the lower the icp. Weird I know but there is evidence that I've seen and one huge 6.0 shop here, Innovative diesel, changed their oil out after a few runs at the track. The next run they actually gained a few tenths in that run. This is from the thicker oil this resulting in a higher icp. The higher the icp the more power your Injectors are making. Icp means power.
 
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Originally Posted By: NattyBoh
Yes but the 10w30 gives me a noticeable and measurable icp drop. Thsts the injection pressure. I have pretty larger than stock injectors so I notice it more than others. Plus a huge icp pump too


OK, now I'm beginning to understand your need for 15w40. Why do you think you need synthetic? It sounds like you want to maintain maximum performance, so changing oil frequently would waste the long-drain benefit of synthetic. Look for a 15w40 that has the best combination of high HTHS, low viscosity index, and low cost. You live in Maryland, so 15w40 should be fine year-round. Has your engine ever had any cold-start romp?

Splitting the difference to a 10w40, AMSoil AMO is a beast of an oil that may be able to resist shearing from the HEUI injection system.
 
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I know it's more of a mindset than anything but synthetic seems to work better and create less sludge, better heat resistance etc.

I get romps on a hot day haha. My Injection stroke is very long. So it takes a minute to get rolling. Again it's far from stock and shows it.

My dad is a dealer for Amsoil and I'm thinking I may have to suck it up. But I can't justify the high cost and quick drains
 
15w40 for synthetic is just a waste of much money..
15w40 dino is very strong actually and many 15w40 is semi synthetic i mean the oil is mixture of synthtic and mineral base.

If you wanna go for synthetic just go 5w40..15w40 is for the one who loves the cheap oil with high quality..

15w40 dino is also robust oil just like delo and delvac mx or 1300..

So why do you need 15w40 synthetic lol
 
I guess I'm spoilt with Petro-Canada Duron.
They have Synthetic 5w40 & 10w40 in both high and low SAPS.
Synthetic blend 15w40 in both high & low SAPS.
Synthetic blend and conventional 15w40 & 10w30, low SAPS CJ-4.
A high performance synthetic 0w40 CJ-4. (not API licensed)
Two choices of 0w30 high SAPS and a 5w30 E6.
Plus medium SAPS, high VI mono-grades.

My favorites from that list is Chevron Delo 400 SAE30 & 40, 15W40 and SD 15W30.
 
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Originally Posted By: NattyBoh
Yes but the 10w30 gives me a noticeable and measurable icp drop. Thsts the injection pressure. I have pretty larger than stock injectors so I notice it more than others. Plus a huge icp pump too
Are you sure the fuel is taking a bit longer to combust when the engine is cool?
 
Originally Posted By: kschachn
Originally Posted By: NattyBoh
Yes but the 10w30 gives me a noticeable and measurable icp drop. Thsts the injection pressure. I have pretty larger than stock injectors so I notice it more than others. Plus a huge icp pump too


You're going to have to explain the connection between your ICP and engine oil viscosity. Are you saying the pump is controlled by engine oil viscosity and a lower one results in lower fuel pressure?


Positive displacement pumps, especially operating at extreme pressures "slip" more when pumping thinner liquids...the pressures involved in some of these injections systems are extraordinarily high (and they are known to chop up VIIs prety badly too in some cases).

http://www.liquiflo.com/v2/files/pdf/Gear_Pump_Basics.pdf
 
Redline, RP, and Amsoil are the top 3. I think Schaeffer's has it as well but good luck finding that stuff anywhere.

You should just keep running the 5w-40, there's no benefit to running 15w-40 in the summer over 5w-40. They are the exact same viscosity at operating temperature, and the 5w will warm up faster which is a good thing for a diesel engine. I run 5w-40 with no issues year round. Anything from -20 to high 90's in the summer. My 7.3 has never ran better, I'd never realized how rough it actually ran on 15w-40 conventional. The difference was shocking and it made me a believer in 5w-40 synthetic diesel oil. Not to mention, it runs a few degrees cooler with the synthetic which I definitely like to see!
 
Originally Posted By: jongies3
They are the exact same viscosity at operating temperature, and the 5w will warm up faster which is a good thing for a diesel engine.



the 5W CAN'T warm up faster, as the 15W will have a higher viscosity DURING the warmup phase, waste more heat, and turn that heat into oil and coolant temperature...the 15W will generate more heat, and waste a tiny bit more fuel.

As to exact same viscosity at temperature, the HTHS between a 5W40 and 15W40 is around 10%, scarcely the same...

Originally Posted By: jongies3
Not to mention, it runs a few degrees cooler with the synthetic which I definitely like to see!


Is that because the 5W40 has a lower operational viscosity, and causes less heat to be generated in shear ?

Then how can it warm up faster (generate more heat) AND generate less heat ?
 
The one OCI I ran a synthetic 15w40, I was completely floored at how zero detectable oil was consumed over the 10K mile interval. 5w40, 5w30 and 0w40 would use 1/2 to 1 quart. (Never did try Redline 5w40 though)
 
That doesn't effect icp. Icp is 100% oil pressure at the Injector pretty much. The icp is higher when the oil is cold, when it heats up, you'll notice a few tenths drop. And even a little more even if the oil is a bit older too
 
Originally Posted By: BobFout
The one OCI I ran a synthetic 15w40, I was completely floored at how zero detectable oil was consumed over the 10K mile interval. 5w40, 5w30 and 0w40 would use 1/2 to 1 quart. (Never did try Redline 5w40 though)
The 15w-40 has a narrower viscosity spread so it is thicker at the 15 part of the spec as compared to a 5w-40 needing more viscosity improvers. The 5 part is a thinner base stock[blend?]
 
Originally Posted By: CT8
Originally Posted By: BobFout
The one OCI I ran a synthetic 15w40, I was completely floored at how zero detectable oil was consumed over the 10K mile interval. 5w40, 5w30 and 0w40 would use 1/2 to 1 quart. (Never did try Redline 5w40 though)
The 15w-40 has a narrower viscosity spread so it is thicker at the 15 part of the spec as compared to a 5w-40 needing more viscosity improvers. The 5 part is a thinner base stock[blend?]


More likely due to the very low NOACK of that oil. I never had the nerve to run a conventional 15w40 to see if it behaved the same (high NOACK, but still molecularly thicker oil)
 
Originally Posted By: BobFout
Originally Posted By: CT8
Originally Posted By: BobFout
The one OCI I ran a synthetic 15w40, I was completely floored at how zero detectable oil was consumed over the 10K mile interval. 5w40, 5w30 and 0w40 would use 1/2 to 1 quart. (Never did try Redline 5w40 though)
The 15w-40 has a narrower viscosity spread so it is thicker at the 15 part of the spec as compared to a 5w-40 needing more viscosity improvers. The 5 part is a thinner base stock[blend?]


More likely due to the very low NOACK of that oil. I never had the nerve to run a conventional 15w40 to see if it behaved the same (high NOACK, but still molecularly thicker oil)

I would've thought conventional 15W40 has lower Noack then a synthetic 5W40 ? CMIIMW.
blush.gif
 
Originally Posted By: zeng
Originally Posted By: BobFout
Originally Posted By: CT8
Originally Posted By: BobFout
The one OCI I ran a synthetic 15w40, I was completely floored at how zero detectable oil was consumed over the 10K mile interval. 5w40, 5w30 and 0w40 would use 1/2 to 1 quart. (Never did try Redline 5w40 though)
The 15w-40 has a narrower viscosity spread so it is thicker at the 15 part of the spec as compared to a 5w-40 needing more viscosity improvers. The 5 part is a thinner base stock[blend?]


More likely due to the very low NOACK of that oil. I never had the nerve to run a conventional 15w40 to see if it behaved the same (high NOACK, but still molecularly thicker oil)

I would've thought conventional 15W40 has lower Noack then a synthetic 5W40 ? CMIIMW.
blush.gif



Conventional CJ-4 15w40s typically have NOACK values between 10% and 13%, the same as most synthetic CJ-4 5w40s.
 
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