I have the 6.0 with the HEUI system, I have already decided to go with a lighter grade either synth or semi synth--no brand decided yet, still working on that-- but would that change the pressure used on the HEUI injector system? In the PCMO forum there was discussion of pressure changes due to going lighter. Does this matter? if it does, would it be good or bad? since this system is sensitive to many things,a change gives me pause. Ford rec's the 15-40 ONLY, according to the dealer, and owners manual, however there is a temp sens chart that shows it being OK at extremely low temps.
Oil pressure changes with grade change?
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dnewton3
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You will find that a 10w-30 works quite well in the HUEI system.
My neighbor runs dino HDEO 10w-30 Rotella in his 6.0PSD. He has good all-year performance. His UOA (posted by me some time far back) was just fine.
Any quality brand of oil will work, and any reasonable grade will work. But I will suggest that you consider T5 in 10w-30 because (at least in my area) it was on sale at WW for $11.99/gallon! You cannot beat a price like that for such convenience.
A note I'll share about vis in the HEUI systems. We've seen (in many UOAs where people actually "dare" to run a 10w-30) that the dreaded "shear monter" that lurks in a PSD only typically attacks the 40 grade products. Put in a 15w-40, 10w-40, or 5w-40, and it will shear down into the 30 grade range at some point. But if you START OUT with a 30 grade, the oil won't shear much, if any at all. It's is almost as if the HEUI simply operates and prefers the 30 grades. If you don't feed it one, it will create one.
The lower vis shows no signs of degredation in regard to wear, as far as UOAs can show. I would not want you to think they have less wear than a 40 grade, as there is no evidence to that fact. I'm saying that the grade difference between a 30 and a 40 apprently has little to no affect on wear in a PSD (or my Dmax).
In regard to your question about the lighter grade and "pressure" that is not a concern either. Pressure (in the case of a hydraulic circuit) is the resistance to flow. Viscosity certainly plays into this, but systems such as the HEUI have a pressure regulator to compensate for these type things. The HEUI, in particular, has a thing called the "IPR" (Injection Pressure Regulator). Any small nuance of pressure change due to vis grade pales in comparison to the actual pressure changes directed by the ECM for HEUI/HPOP operation.
What you "gain" from the lighter grade is an engine that starts a bit easier in winter, and does not "romp" with a thick oil at idle.
Fear not the lighter grade.
P.S. - I also use dino HDEO 10w-30 in my Dmax, and had an excellent UOA, even after heavy towing for 6k miles.
My neighbor runs dino HDEO 10w-30 Rotella in his 6.0PSD. He has good all-year performance. His UOA (posted by me some time far back) was just fine.
Any quality brand of oil will work, and any reasonable grade will work. But I will suggest that you consider T5 in 10w-30 because (at least in my area) it was on sale at WW for $11.99/gallon! You cannot beat a price like that for such convenience.
A note I'll share about vis in the HEUI systems. We've seen (in many UOAs where people actually "dare" to run a 10w-30) that the dreaded "shear monter" that lurks in a PSD only typically attacks the 40 grade products. Put in a 15w-40, 10w-40, or 5w-40, and it will shear down into the 30 grade range at some point. But if you START OUT with a 30 grade, the oil won't shear much, if any at all. It's is almost as if the HEUI simply operates and prefers the 30 grades. If you don't feed it one, it will create one.
The lower vis shows no signs of degredation in regard to wear, as far as UOAs can show. I would not want you to think they have less wear than a 40 grade, as there is no evidence to that fact. I'm saying that the grade difference between a 30 and a 40 apprently has little to no affect on wear in a PSD (or my Dmax).
In regard to your question about the lighter grade and "pressure" that is not a concern either. Pressure (in the case of a hydraulic circuit) is the resistance to flow. Viscosity certainly plays into this, but systems such as the HEUI have a pressure regulator to compensate for these type things. The HEUI, in particular, has a thing called the "IPR" (Injection Pressure Regulator). Any small nuance of pressure change due to vis grade pales in comparison to the actual pressure changes directed by the ECM for HEUI/HPOP operation.
What you "gain" from the lighter grade is an engine that starts a bit easier in winter, and does not "romp" with a thick oil at idle.
Fear not the lighter grade.
P.S. - I also use dino HDEO 10w-30 in my Dmax, and had an excellent UOA, even after heavy towing for 6k miles.
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Great! I was wondering about the regulation of pressure and how it would affect the system, but if it's a relatively minor influence with the regulation system, then I am sold! I am going to give it a shot here shortly! just wanted to make sure that it wouldnt be yet another variable playing into the injector actuation, and the dealer says "15-40, only--although you can find different specs for different temps. Thanks alot!
dnewton3
Staff member
HDEO oils are the last bastion of the 'ol-skool' thicker is better mentality.
Some of us dare to run the ligher grades, and see no performance loss.
And, ask your dealer a few questions and see what his answers are.
1) if thicker is better for wear protection, then why does the newer PSD call for the "normal" oil to be a 30 grade? Why do UOAs show no statistically significant differences in wear when comparing a 30 grade to a 40 grade?
2) since pressure is the resistance to flow, would not better "flow" from a thinner oil not make the HEUI actually respond more efficiently and quickly to the ECM commands? (BTW, this is excatly why the HEUI does not "romp", or at least "romps" less, in winter with a thinner oil. Thick oils do not react as quickly, because the higher pressure is actually a higher resistance to flow, and it's the oil flow in the HEUI that dictates how accurately the injectors respond to the ECM commands!).
Your service man might be stuck mentally in the 1970s, but you don't have to be.
Some of us dare to run the ligher grades, and see no performance loss.
And, ask your dealer a few questions and see what his answers are.
1) if thicker is better for wear protection, then why does the newer PSD call for the "normal" oil to be a 30 grade? Why do UOAs show no statistically significant differences in wear when comparing a 30 grade to a 40 grade?
2) since pressure is the resistance to flow, would not better "flow" from a thinner oil not make the HEUI actually respond more efficiently and quickly to the ECM commands? (BTW, this is excatly why the HEUI does not "romp", or at least "romps" less, in winter with a thinner oil. Thick oils do not react as quickly, because the higher pressure is actually a higher resistance to flow, and it's the oil flow in the HEUI that dictates how accurately the injectors respond to the ECM commands!).
Your service man might be stuck mentally in the 1970s, but you don't have to be.
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Originally Posted By: wayniac
I have the 6.0 with the HEUI system.... Ford rec's the 15-40 ONLY, according to the dealer, and owners manual, however there is a temp sens chart that shows it being OK at extremely low temps.
WRONG.
Read this entire page and count the total number of Motorcraft diesel oils spec'd for the 6.0.
I have the 6.0 with the HEUI system.... Ford rec's the 15-40 ONLY, according to the dealer, and owners manual, however there is a temp sens chart that shows it being OK at extremely low temps.
WRONG.
Read this entire page and count the total number of Motorcraft diesel oils spec'd for the 6.0.
i also have a 6.0 ('07) and run 10w-30 year around, towing & hauling upto 4,000# in the bed.
i have several uoa's posted in thhe uoa forum with excellent results.
your owners manual states 10w-30 IS accecptable, and as dnewton already stated the 6.0 injection system almost prefers it.
i'm on my 4th oci now with 10w-30 and i'm running out to 7,500mi oci, just check out the uoa section and you will see for yourself.
there are many ford dealerships only putting 10w-30 in the 6.0's they service to solve hard cold starts at the reccomendation of a TSB issued by Ford
i have several uoa's posted in thhe uoa forum with excellent results.
your owners manual states 10w-30 IS accecptable, and as dnewton already stated the 6.0 injection system almost prefers it.
i'm on my 4th oci now with 10w-30 and i'm running out to 7,500mi oci, just check out the uoa section and you will see for yourself.
there are many ford dealerships only putting 10w-30 in the 6.0's they service to solve hard cold starts at the reccomendation of a TSB issued by Ford
I was going by the service dept. here in Houston, and the chart with vis and temp specs in my owners man. I do not have an updated manual, and I should probably get one along with all the new service bulletins (havent read them all). Sorry if I was going in ill-prepared. I just looked at those, listened to him, and looked at the certifications on the bottle and in the manual. Another reason to be here!!!
dnewton3
Staff member
Originally Posted By: STG
Originally Posted By: wayniac
I have the 6.0 with the HEUI system.... Ford rec's the 15-40 ONLY, according to the dealer, and owners manual, however there is a temp sens chart that shows it being OK at extremely low temps.
WRONG.
Read this entire page and count the total number of Motorcraft diesel oils spec'd for the 6.0.
I suspect what he was trying to say is that the "recommended" vis from his dealer was to use only 15w-40. IOW, the "dealer says that Ford says ..." which is, obviously, open to a lot of mis-information. Ford clearly approves multiple product grades for the 6.0L.
Like I said, some portions of the diesel industry are still locked in the 15w-40 mentality. Others are beginning to open their eyes. I have yet to see any UOA example where a lighter grade resulted in high wear and detrimental abuse. Surely, one must make certain to use a lube that is HDEO rated when choosing a lighter grade; typical PCMO 10w-30 won't cut it in a diesel. But the market specific products perform well.
In central TX, I don't know that the lighter grade will really make a lot of different in cold starts over a 15w-40; there may not be much of an advantage in that area. But for us folks in the colder parts of North America, the 10w-30 really helps quiet the romp of HEUI in both the older 7.3L and 6.0L PSDs. The avearge low in Houston is only 45 deg F in Jan; that's not cold at all, and 15w-40 should start up just fine. There really isn't as much temperature variation in that area, contrasted to the mid-west.
Example:
Houston average low is 45, and average high is 95; a 50 degree spread
Indy average low is 18, high is 85; a 67 degree spread. And we do get into the high 90's often as well as down below zero a few times each year.
If I were the OP, I would choose whatever product I could find on sale, because his environmental concerns are minimal. 10w-30 or 15w-40 would work equally well in his area, most likely.
Coming full circle all the way back to his original question, the pressure difference between the 40 and 30 grade won't make any real differnce in his area. He might try it and really like it; good for him. He may decide he does not like it; that's ok too. Fundementally, it won't hurt his ride to use the lighter grade, and he may get a slight bit better starting. The ECM will direct the IPR to compensate for a range far greater than this little nuance will affect the system anyway.
Originally Posted By: wayniac
I have the 6.0 with the HEUI system.... Ford rec's the 15-40 ONLY, according to the dealer, and owners manual, however there is a temp sens chart that shows it being OK at extremely low temps.
WRONG.
Read this entire page and count the total number of Motorcraft diesel oils spec'd for the 6.0.
I suspect what he was trying to say is that the "recommended" vis from his dealer was to use only 15w-40. IOW, the "dealer says that Ford says ..." which is, obviously, open to a lot of mis-information. Ford clearly approves multiple product grades for the 6.0L.
Like I said, some portions of the diesel industry are still locked in the 15w-40 mentality. Others are beginning to open their eyes. I have yet to see any UOA example where a lighter grade resulted in high wear and detrimental abuse. Surely, one must make certain to use a lube that is HDEO rated when choosing a lighter grade; typical PCMO 10w-30 won't cut it in a diesel. But the market specific products perform well.
In central TX, I don't know that the lighter grade will really make a lot of different in cold starts over a 15w-40; there may not be much of an advantage in that area. But for us folks in the colder parts of North America, the 10w-30 really helps quiet the romp of HEUI in both the older 7.3L and 6.0L PSDs. The avearge low in Houston is only 45 deg F in Jan; that's not cold at all, and 15w-40 should start up just fine. There really isn't as much temperature variation in that area, contrasted to the mid-west.
Example:
Houston average low is 45, and average high is 95; a 50 degree spread
Indy average low is 18, high is 85; a 67 degree spread. And we do get into the high 90's often as well as down below zero a few times each year.
If I were the OP, I would choose whatever product I could find on sale, because his environmental concerns are minimal. 10w-30 or 15w-40 would work equally well in his area, most likely.
Coming full circle all the way back to his original question, the pressure difference between the 40 and 30 grade won't make any real differnce in his area. He might try it and really like it; good for him. He may decide he does not like it; that's ok too. Fundementally, it won't hurt his ride to use the lighter grade, and he may get a slight bit better starting. The ECM will direct the IPR to compensate for a range far greater than this little nuance will affect the system anyway.
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Originally Posted By: dnewton3
Like I said, some portions of the diesel industry are still locked in the 15w-40 mentality. Others are beginning to open their eyes.
I have seen that even in some agricultural equipment as of late. A buddy's diesel JD tractor (and his Kubota lawn mower, which he sold) calls for 10w-30. I was a tad surprised. He had asked me what I thought, and I said "15w-40 - what else would it use?" I also told him we should check the manuals, and it was good that we did.
Like I said, some portions of the diesel industry are still locked in the 15w-40 mentality. Others are beginning to open their eyes.
I have seen that even in some agricultural equipment as of late. A buddy's diesel JD tractor (and his Kubota lawn mower, which he sold) calls for 10w-30. I was a tad surprised. He had asked me what I thought, and I said "15w-40 - what else would it use?" I also told him we should check the manuals, and it was good that we did.
Speaking of oil pressure, going from a 15W40to a 10W30 in my 6.9L Ford IDI diesel was about 4 psi of oil pressure warmed up... nuthin! The drop was similar in a 2810 Dagenham Ford tractor. The change to 10W30 on the tractor was the difference between starting and not starting in the winter, unplugged. I have a half mile long lane and I have to KNOW it will start, even if i have to leave it unplugged for some reason. With the 15W40, it didn't always spin over fast enough to start... and you've only got so much cranking available from the battery when it's cold. Yeah, I could use 5W40 syn, but a) it's almost double the money, b) I really don't need a 40 grade in that small tractor and c) I use 10W30 in a whole bunch of other equipment around here, so it consolidates my oil stocks.
Ok, I changed to T5 10-30, and there was a difference. The clacking was quieter, and the starts were faster, I have to do the math to verify the MPG inc that the computer indicates, but it seems a touch more responsive. To me there was a noticable difference btwn T5 and the motorcraft 15-40. saved some oil for UOA, and will do some comparing with the T5.
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