...in a diesel engine which usually calls for an 15w40? I have seen UOA's on here by "patman" and "arkapig" using HDEO 10w30's in their duramax engines with quite stellar results. This throws my logic about oils right out the window, as in my mind at least with a diesel engine you have severe loads placed on journal bearings due to the diesel engines torque, and I thought in a situation like this you would need the protection of a 40 weight oil to prevent metal to metal contact? What am I missing here? Is it the additive package which takes effect when/if you do get metal to metal contact? I do know that you have better resistance against shearing with a 10w30 vs a 15w40, but am still confused. I have even heard of some duramax owners in the brutal heat of texas using rotella T5 10w30 year round AND towing! That would make me a bit skeerd.
Confused how a HDEO 10W30 can do well....
- Thread starter Ponch
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JHZR2
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So little time is truly highly loaded that it may make less of a difference for passenger trucks than other applications. Also has to be related to ambient temperatures and such. Lots of vehicles have some temperature range where a 30wt is more than acceptable.
The majors have been working to get a good 30wt HDEO out for a long time. There are still some challenges due to longevity for true HD applications, but passenger vehicles just dont have that use profile.
The majors have been working to get a good 30wt HDEO out for a long time. There are still some challenges due to longevity for true HD applications, but passenger vehicles just dont have that use profile.
Hi,
it all comes down to using the recomended viscosity for the ambient temperature "spread" likely to be encountered. Many High Speed Heavy Diesel (HSHD) engines have a requirement for a minimum HTHS vis. of 3.7cP
This data from CAT may assist you:
SAE 10W-30 is the preferred viscosity grade for the following diesel engines when the ambient temeprature is above -18C (40F) and below 40C (104F)
C7, C9, C-9, 3116 and 3126
The recommended viscosities for all other engines in the CAT family are:
0W-40 - temperature from -40C (-40F) to 40C (104F)
5W-40 - temperatures from -30 (-22F) to 50C (122F)
10W-40 - temperatures from -18C (0F) to 50C (122F)
15W-40 - temperatures from -9.5C (15F) to 50C (122F)
As well CAT mandate the use of synthetic base oils below -30C (-22F) and the use of the highest viscosity that meets the cold start needs (SAE40 over SAE30 where both have a 0W rating)
CAT have had the most comprehensive lubricanst specifications of any NA Manufacturer - and since the 1930s!
So with mid-range diesels it is best to follow the recommended viscosity - but the modern 10W-30 HDEOs are very robust oils indeed. I would use them with confidence
it all comes down to using the recomended viscosity for the ambient temperature "spread" likely to be encountered. Many High Speed Heavy Diesel (HSHD) engines have a requirement for a minimum HTHS vis. of 3.7cP
This data from CAT may assist you:
SAE 10W-30 is the preferred viscosity grade for the following diesel engines when the ambient temeprature is above -18C (40F) and below 40C (104F)
C7, C9, C-9, 3116 and 3126
The recommended viscosities for all other engines in the CAT family are:
0W-40 - temperature from -40C (-40F) to 40C (104F)
5W-40 - temperatures from -30 (-22F) to 50C (122F)
10W-40 - temperatures from -18C (0F) to 50C (122F)
15W-40 - temperatures from -9.5C (15F) to 50C (122F)
As well CAT mandate the use of synthetic base oils below -30C (-22F) and the use of the highest viscosity that meets the cold start needs (SAE40 over SAE30 where both have a 0W rating)
CAT have had the most comprehensive lubricanst specifications of any NA Manufacturer - and since the 1930s!
So with mid-range diesels it is best to follow the recommended viscosity - but the modern 10W-30 HDEOs are very robust oils indeed. I would use them with confidence
JHZR2
Staff member
Doug,
What if you dont have a CAT? There are similar temp/visc plots for other engines. Here is a newer and older MB diesel (LD) chart:
What I dont exactly get from the CAT charts is how a 0w-40 isnt "good enough" for 50C conditions while a 5w-40 or 10w-40 or 15w-40 is. Perhaps it is a VII issue, though any 0w-40 would be syn. A 40wt is a 40wt, whether it pumps at some low temperature or a different low temperature. Why vary the upper temp range for the 0w- versus the others?
What if you dont have a CAT? There are similar temp/visc plots for other engines. Here is a newer and older MB diesel (LD) chart:
What I dont exactly get from the CAT charts is how a 0w-40 isnt "good enough" for 50C conditions while a 5w-40 or 10w-40 or 15w-40 is. Perhaps it is a VII issue, though any 0w-40 would be syn. A 40wt is a 40wt, whether it pumps at some low temperature or a different low temperature. Why vary the upper temp range for the 0w- versus the others?
I would use a 5w40, that should cover all bases for you, I think that is in the manual??
Hi,
JHZR2 - I only published the CAT data as a "prime" example
of the justification for a 10W-30 HDEO. It is not so long ago that a SAE20W-20 was prescribed in some applications
Many Euro HSHD engines have been using SAE30 lubricants for some years now - 5W-30 and 10W-30 semi-synthetics in most cases - and over long OCIs
Detroit Diesel (7SE270) also only recommend a 15W-40 except for cold starts and 10W-30 for -20C (-4F) to 35C (95F).
Their minimum HTHS viscosity is 3.7cP
DD only recommend SAE40 lubricants above 40C. A 5W-40 can be used down to -25C (-13F)and well above 40C (104F)
In answering your query I suspect that it is a VI and HTHS viscosity issue considering that the CAT engines operate in great extremes around the Globe. They also operate in heavy duty and continuous cycles. My two youngest Sons are CAT trained and the use of precribed lubricant viscosities is embedded in their minds!
JHZR2 - I only published the CAT data as a "prime" example
of the justification for a 10W-30 HDEO. It is not so long ago that a SAE20W-20 was prescribed in some applications
Many Euro HSHD engines have been using SAE30 lubricants for some years now - 5W-30 and 10W-30 semi-synthetics in most cases - and over long OCIs
Detroit Diesel (7SE270) also only recommend a 15W-40 except for cold starts and 10W-30 for -20C (-4F) to 35C (95F).
Their minimum HTHS viscosity is 3.7cP
DD only recommend SAE40 lubricants above 40C. A 5W-40 can be used down to -25C (-13F)and well above 40C (104F)
In answering your query I suspect that it is a VI and HTHS viscosity issue considering that the CAT engines operate in great extremes around the Globe. They also operate in heavy duty and continuous cycles. My two youngest Sons are CAT trained and the use of precribed lubricant viscosities is embedded in their minds!
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dnewton3
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I'm one of the "daring" Dmax owners that run dino Rotella 10w-30 year round. And I tow my full size travel trailer every summer, in the heat, out west, in the mountains, at high speeds.
Bearing protection comes from a combination of several things; the oil pressure, the oil volume, the bearing clearance and bearing load are the main contributors. Typically, more than one 'grade' of oil vis is acceptable. As long as your volume and pressure are decent, and the oil vis is acceptable, the bearings will be fine. You asked specifically about a Dmax; they are some of the best wearing light-duty diesels out there. But I've even see good performance from dino 10w-30 HDEO in my neighbors 6.0L PSD; his UOA shows similar results as mine.
And here is my UOA proof from last year: http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1669271&page=1
Not much to debate when you see the results firsthand. Got another load of dino 10w-30 in there right now.
Here is my neighbor's 6.0 PSD: http://www.bobistheoilguy.com/forums/ubb...rue#Post1118516
I OCI each fall, so I'll likely post up another UOA about a year from now to see how the oil holds up, although I expect little will change. The only "change" I might make next year is switching to T5 10w-30. I typically get dino Rotella for $10/gallon, but recently saw T5 for $11.49/gallon at W/M. Might "splurge" and spend the extra $4.50 for three gallons to see the performance difference, if any ...
Bearing protection comes from a combination of several things; the oil pressure, the oil volume, the bearing clearance and bearing load are the main contributors. Typically, more than one 'grade' of oil vis is acceptable. As long as your volume and pressure are decent, and the oil vis is acceptable, the bearings will be fine. You asked specifically about a Dmax; they are some of the best wearing light-duty diesels out there. But I've even see good performance from dino 10w-30 HDEO in my neighbors 6.0L PSD; his UOA shows similar results as mine.
And here is my UOA proof from last year: http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1669271&page=1
Not much to debate when you see the results firsthand. Got another load of dino 10w-30 in there right now.
Here is my neighbor's 6.0 PSD: http://www.bobistheoilguy.com/forums/ubb...rue#Post1118516
I OCI each fall, so I'll likely post up another UOA about a year from now to see how the oil holds up, although I expect little will change. The only "change" I might make next year is switching to T5 10w-30. I typically get dino Rotella for $10/gallon, but recently saw T5 for $11.49/gallon at W/M. Might "splurge" and spend the extra $4.50 for three gallons to see the performance difference, if any ...
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JHZR2
Staff member
dnewton, thought rotella 10w-30 was T5 10w-30, just slightly renewed product lines. Is that not the case and you have access to two 10w30 rotella product lines? Maybe I read your post wrong...
I've been pondering 30wt for a long time in my Dodge Cummins...after about 5 years of so many other issues, I think I am just going to switch to the oil I want to use...and use it with confidence. UOA will tell. I just do not truly believe that it is going to make a difference in the average user/owner's vehicle lifespan.
when the 5.9 cummins was intially introduced in the late 80's the only viscosity recommended was 10w-30, atleast in marine applications. at the time everyone was using straight 30wt in everything except the detroits, so a 10w-30 would have been a huge improvement in cold starts.
I don't think, atleast in the 2000's anyways, that the dodge use 5.9 even mention 10w-30, but I really don't see an issue using it year around. If I were expecting 100f+ ambient temps I would switch back to 15w-40 though.
I, along with a few listed above am a 10w-30 "convert" in my 6.0 powerstroke with a few uoa's posted in the hdeo uoa section. the 10w-30 has shown, atleast in my useage, to return excellent uoa results, no make-up oil needed between oc's, excellent cold weather start-ups, virtually no shearing of viscosity (6.0's are known for shearing 40wt. to 30wt. in no time), and at half the price of the cheapest 5w-40 I see it as a no-brainer.
I don't think, atleast in the 2000's anyways, that the dodge use 5.9 even mention 10w-30, but I really don't see an issue using it year around. If I were expecting 100f+ ambient temps I would switch back to 15w-40 though.
I, along with a few listed above am a 10w-30 "convert" in my 6.0 powerstroke with a few uoa's posted in the hdeo uoa section. the 10w-30 has shown, atleast in my useage, to return excellent uoa results, no make-up oil needed between oc's, excellent cold weather start-ups, virtually no shearing of viscosity (6.0's are known for shearing 40wt. to 30wt. in no time), and at half the price of the cheapest 5w-40 I see it as a no-brainer.
I have certainly been a fan of 10w30 HD Diesel Oil for years, and have used it exclusively in my 2004 Ford 6.0 powerstroke, the Shell Rotella T5 10w30 and the Amsoil ACD 10w30 diesel synthetic. Both performed well in testing, with the amsoil retaining a much higher TBN over several thousands of miles.
Earlier this year, I exchanged the 6.0 powerstroke in for an '06 Duramax LBZ that had 38,000 miles on the odometer....the previous owner used Royal Purple 15w40. As soon as I got it, I put in Amsoil 10w30 ACD diesel synthetic and a mobil 1 M1-303 oil filter. My mileage increased 1mpg, runs smoother, which is not huge but makes a difference.
I use the Amsoil ACD 10w30 diesel synthetic year round, and live in texas and tow what ever I want to tow and not one issue. Keep in mind, the Duramax is very easy on oil, but you still should use a high quality oil to protect a $13,000 motor
Earlier this year, I exchanged the 6.0 powerstroke in for an '06 Duramax LBZ that had 38,000 miles on the odometer....the previous owner used Royal Purple 15w40. As soon as I got it, I put in Amsoil 10w30 ACD diesel synthetic and a mobil 1 M1-303 oil filter. My mileage increased 1mpg, runs smoother, which is not huge but makes a difference.
I use the Amsoil ACD 10w30 diesel synthetic year round, and live in texas and tow what ever I want to tow and not one issue. Keep in mind, the Duramax is very easy on oil, but you still should use a high quality oil to protect a $13,000 motor
Originally Posted By: Doug Hillary
I suspect that it is a VI and HTHS viscosity issue considering that the CAT engines operate in great extremes around the Globe. They also operate in heavy duty and continuous cycles.
I beleive that to be the case...
Our new 975c challenger(that were able see being assembled touring the factory was cool) has a 600hp C18. Caterpillar told us for the ambient temps we were operating this unit in to only use an approved 15w40 during the warranty period and even after.
that said the owners manual lists everything from a 10w30,30w to a 15w40 that could be used in this monster,unreal a 10w30!
I suspect that it is a VI and HTHS viscosity issue considering that the CAT engines operate in great extremes around the Globe. They also operate in heavy duty and continuous cycles.
I beleive that to be the case...
Our new 975c challenger(that were able see being assembled touring the factory was cool) has a 600hp C18. Caterpillar told us for the ambient temps we were operating this unit in to only use an approved 15w40 during the warranty period and even after.
that said the owners manual lists everything from a 10w30,30w to a 15w40 that could be used in this monster,unreal a 10w30!
dnewton3
Staff member
Originally Posted By: JHZR2
dnewton, thought rotella 10w-30 was T5 10w-30, just slightly renewed product lines. Is that not the case and you have access to two 10w30 rotella product lines? Maybe I read your post wrong...
The dino is "Triple Protection" 10w-30 and 15w-40.
The semi-syn is the T5, available in 10w-30, 10w-40.
(There are, of course, fleet and mono-grades, but that wasn't the topic).
My being in a semi-rural area, there are several farm-supply stores, therefore lots of HDEO choices in my area. I've been able to get dino Triple Protection 10w-30 Rotella for years. I have, and do, use the dino 10w-30 in much of my equipment; been very successful.
dnewton, thought rotella 10w-30 was T5 10w-30, just slightly renewed product lines. Is that not the case and you have access to two 10w30 rotella product lines? Maybe I read your post wrong...
The dino is "Triple Protection" 10w-30 and 15w-40.
The semi-syn is the T5, available in 10w-30, 10w-40.
(There are, of course, fleet and mono-grades, but that wasn't the topic).
My being in a semi-rural area, there are several farm-supply stores, therefore lots of HDEO choices in my area. I've been able to get dino Triple Protection 10w-30 Rotella for years. I have, and do, use the dino 10w-30 in much of my equipment; been very successful.
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JHZR2
Staff member
Good to know... I just have the availability at AZ or WM generally. Thanks!
You guys are awesome! Thanks for all of the in depth info! I might end up going the T5 10w30 route year round....I know that in stock form the duramaxes are easy on oil, but I do have mine tuned (bullydog programmer), so that is what makes me nervous still.
Originally Posted By: Ponch
You guys are awesome! Thanks for all of the in depth info! I might end up going the T5 10w30 route year round....I know that in stock form the duramaxes are easy on oil, but I do have mine tuned (bullydog programmer), so that is what makes me nervous still.
How is the truck used 90% of the time? tow/haul?, little bit?/ allot?
You guys are awesome! Thanks for all of the in depth info! I might end up going the T5 10w30 route year round....I know that in stock form the duramaxes are easy on oil, but I do have mine tuned (bullydog programmer), so that is what makes me nervous still.
How is the truck used 90% of the time? tow/haul?, little bit?/ allot?
Quote:
with a diesel engine you have severe loads placed on journal bearings due to the diesel engines torque,
Not exactly. Torque is a twisting force which does not impact the crankshaft bearing unless the crank seriously deflects. The load is from the push of the pistons.
Quote:
Bearing protection comes from a combination of several things; the oil pressure, the oil volume, the bearing clearance and bearing load are the main contributors.
Not exactly. Bearing protection is from the hydrodynamic wedge of oil built up due to rotation of the journal in the bearing. Oil pressure & supply volume just makes up for loss of oil out the ends of the bearing. Ditto for bearing clearance. Other things equal, higher viscosity oil has higher film strength for greater resistance to breaking down the hydrodynamic wedge of oil that holds the journal away from the bearing.
Much depends on the size of the bearing vs. the load. A very large diesel engine of 7,500 hp per cylinder has 30 wt oil in the crankcase. This works due to the area of the bearing vs. the load. "In the hydrodynamic state a lubrication "wedge" forms, which lifts the journal."
http://en.wikipedia.org/wiki/Journal_bearing#Fluid_lubrication
with a diesel engine you have severe loads placed on journal bearings due to the diesel engines torque,
Not exactly. Torque is a twisting force which does not impact the crankshaft bearing unless the crank seriously deflects. The load is from the push of the pistons.
Quote:
Bearing protection comes from a combination of several things; the oil pressure, the oil volume, the bearing clearance and bearing load are the main contributors.
Not exactly. Bearing protection is from the hydrodynamic wedge of oil built up due to rotation of the journal in the bearing. Oil pressure & supply volume just makes up for loss of oil out the ends of the bearing. Ditto for bearing clearance. Other things equal, higher viscosity oil has higher film strength for greater resistance to breaking down the hydrodynamic wedge of oil that holds the journal away from the bearing.
Much depends on the size of the bearing vs. the load. A very large diesel engine of 7,500 hp per cylinder has 30 wt oil in the crankcase. This works due to the area of the bearing vs. the load. "In the hydrodynamic state a lubrication "wedge" forms, which lifts the journal."
http://en.wikipedia.org/wiki/Journal_bearing#Fluid_lubrication
dnewton3
Staff member
" Not exactly. Bearing protection is from the hydrodynamic wedge of oil built up due to rotation of the journal in the bearing. Oil pressure & supply volume just makes up for loss of oil out the ends of the bearing. Ditto for bearing clearance. Other things equal, higher viscosity oil has higher film strength for greater resistance to breaking down the hydrodynamic wedge of oil that holds the journal away from the bearing. "
Yes, that wedge is what floats the shaft above the bearing. However, that hydrodynamic wedge would not be present if the oil pressure and volume were insufficient, or if the load were able to over-come the barrier due to pure force, or if the clearance were too large allowing too much oil to escape, etc. It is these things working in concert that make the bearing and rotational shaft (crank, cam, etc) live together in harmony.
And I guess if we're going to get picky (not on you, but the drawing you posted). That "journal" as called out in the picture is actually the shaft. Because of the way the picture is labeled, you were correct to say that the journal rotates in the bearing. But the picture is really incorrect. The "journal" is just the word we use for the interactive relationship between the bearing and the shaft. (Think of the words "door" and "door way". The door is a physical thing, but the "door way" is just the hole you walk through). The "bearing" and "shaft", when placed together, make a "journal". So the "journal" does not rotate; the "shaft" does.
Yes, that wedge is what floats the shaft above the bearing. However, that hydrodynamic wedge would not be present if the oil pressure and volume were insufficient, or if the load were able to over-come the barrier due to pure force, or if the clearance were too large allowing too much oil to escape, etc. It is these things working in concert that make the bearing and rotational shaft (crank, cam, etc) live together in harmony.
And I guess if we're going to get picky (not on you, but the drawing you posted). That "journal" as called out in the picture is actually the shaft. Because of the way the picture is labeled, you were correct to say that the journal rotates in the bearing. But the picture is really incorrect. The "journal" is just the word we use for the interactive relationship between the bearing and the shaft. (Think of the words "door" and "door way". The door is a physical thing, but the "door way" is just the hole you walk through). The "bearing" and "shaft", when placed together, make a "journal". So the "journal" does not rotate; the "shaft" does.
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My fiancee has run Motorcraft 10W-30 diesel oil in her 2003 Ford Superduty with the 6.0 since day one. That is what the dealer used and recommended at the time. Truck now has 74,000 miles on it with no problems.
Wayne
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