06 GMC LBZ Duramax

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Changed the oil at the time due to a cold snap & felt terrible hearing the motor waiting for the 15/40 Delvac to circulate. At the time, I was 2 quarts shy on Delvac so I had my mechanic throw in 15/40 Rotella he had on hand. I'm wondering if that had any bearing on the bump in Calcium & Phosphorus.

My next sample will be with Rotella T5 10/30. I'm interested to see the difference. Results are from Blackstone. Thanks for any input.

MI/HR on Oil: 9,617, 10,281, 6,350
MI/HR on Unit: 111,980,102,363, 98,432
Sample Date: 01/06/12, 03/18/11, 12/30/10
Make Up Oil Added: 0 qts, 0 qts, 0 qts

ALUMINUM: 2, 3, 1
CHROMIUM: 0, 0, 0
IRON: 7, 10, 5
COPPER: 2, 2, 1
LEAD: 1, 1, 0
TIN: 0, 0, 1
MOLYBDENUM: 46, 51, 37
NICKEL: 0, 0, 0
MANGANESE: 0, 0, 0
SILVER: 0, 0, 0
TITANIUM: 0, 0, 0
POTASSIUM: 4, 3, 1
BORON: 39, 45, 39
SILICON: 4, 4, 4
SODIUM: 5, 6, 5
CALCIUM: 1604, 1389, 1216
MAGNESIUM: 856, 843, 762
PHOSPHORUS: 1063, 950, 803
ZINC: 1238, 1134, 801
BARIUM: 0, 0, 0

SUS Viscosity @ 210°F: 74.9, 74, 74.2
cSt Viscosity @ 100°C: 14.23, 13.99, 14.04
Flashpoint in °F: 425, 440, 415
Fuel %: Antifreeze %: 0, 0, 0
Water %: 0, 0, 0
Insolubles %: .2, .2, .2
TBN: 8.5, 7.6, 8.8
 
What parts on those engines actually wear? Great UOA!

I am interested in the 10w30 UOA as well. I heard that 10w30 is the new diesel oil weight. Or will be soon.
 
Typical Dmax UOA ... Boring = Excellent. As long as you use a spec'd HDEO, these engines simply don't care what brand/grade/base stock you dump in the crankcase.

By the looks of things, you could have gone WELL past that 9-10k mile mark.

Interesting to note something here: What you "hear" turns into what your mind interprets. You believed that the 15w-40 Delvac was causing the engine to strain at start up (for a lack of a better term), right? And yet the wear results show no increase in wear issues whatsoever. The 15w-40 is rated as "preferred" by GM down to zero deg F. My point is that many people fear engine damage from thicker fluids in winter, but much more often than not, there is never any damage that materializes. The "fear" people have is all imagined; it rarely if ever manifests into reality.

Nothing wrong with using the 10w-30 T5. I, myself, use dino Rotella 10w-30; have had great results with it as well.

I've become a firm believer that the Dmax is simply one of the better-designed light-duty diesel engines of all time when it comes to lube system performance and wear results. Time after time we see any number of various lubes all return the same excellent results. That is a compliment to both the lubes of today, and the design of the engine.


Please let us know which lube brand/grade was used for each UOA; or were they all the same of Devlac 15-w40?
 
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All were with Devlac 15-w40. Never thought to look at it that way. The sound definitely irks me. I paid for piece of mind on that one. I'm going to take the T5 to 90% on the DIC and sample from there.
 
Great UOA's "BigBluLbz" I have the same truck/engine. As dave mentioned above..these engines simply do not care what oil you use as long as it is specd accordingly. -Ponch
 
Originally Posted By: dnewton3
Typical Dmax UOA ... Boring = Excellent. As long as you use a spec'd HDEO, these engines simply don't care what brand/grade/base stock you dump in the crankcase.

By the looks of things, you could have gone WELL past that 9-10k mile mark.

Interesting to note something here: What you "hear" turns into what your mind interprets. You believed that the 15w-40 Delvac was causing the engine to strain at start up (for a lack of a better term), right? And yet the wear results show no increase in wear issues whatsoever. The 15w-40 is rated as "preferred" by GM down to zero deg F. My point is that many people fear engine damage from thicker fluids in winter, but much more often than not, there is never any damage that materializes. The "fear" people have is all imagined; it rarely if ever manifests into reality.

Nothing wrong with using the 10w-30 T5. I, myself, use dino Rotella 10w-30; have had great results with it as well.

I've become a firm believer that the Dmax is simply one of the better-designed light-duty diesel engines of all time when it comes to lube system performance and wear results. Time after time we see any number of various lubes all return the same excellent results. That is a compliment to both the lubes of today, and the design of the engine.


Please let us know which lube brand/grade was used for each UOA; or were they all the same of Devlac 15-w40?


I agree thicker in diesel is different than thicker in gas. I run a 15w40 delo dino in my 2001 t444e in winter or summer and i cant notice any difference. even my little isuzus get the same and my huge cummins and cats get the same oil and they all like it. I also run the delo in my small 4-cycle engines and they seem to show less wear (not very scientific) I notice my 3 generators like a diesel rated oil as well.

its weird to see one engine sooo easy on oil and the next engine beat the heck out of it and sludge up if someone even says extended OCI. I wonder what makes the D-max easy on oil. Less shear points or heat maybe. I know its not excessive amounts in the sump, but i would love to find out.
 
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I'm a believer. I shopped heavily and settled on the Dmax for my tow vehicle.

Easy on the oil indicates a superior internal design that puts oil where it's needed and has adequate bearing sizes, etc.

It's so smooth and quiet it's hard to believe it's a diesel.
 
Originally Posted By: SteveSRT8
I'm a believer. I shopped heavily and settled on the Dmax for my tow vehicle.

Easy on the oil indicates a superior internal design that puts oil where it's needed and has adequate bearing sizes, etc.

It's so smooth and quiet it's hard to believe it's a diesel.


True. I came from an 02 7.3. I loved the engine & truck equally. But after I got rid of it, big mistake, I got a car. Now I'm back in this truck. There is only 4 years separating the 2 vehicles, but the technology is light years ahead.
 
Looks great! I hope my number are that good. My OLM is at 1% 73112mi to 84989mi. I hope sample to oil on the change. Been running RT6 since 14000mi. I recently drove from Alaska to Georgia on mild EFI Live tune pulling a 7300 cargo trailer.
 
Originally Posted By: dnewton3
Interesting to note something here: What you "hear" turns into what your mind interprets. You believed that the 15w-40 Delvac was causing the engine to strain at start up (for a lack of a better term), right? And yet the wear results show no increase in wear issues whatsoever. The 15w-40 is rated as "preferred" by GM down to zero deg F. My point is that many people fear engine damage from thicker fluids in winter, but much more often than not, there is never any damage that materializes. The "fear" people have is all imagined; it rarely if ever manifests into reality.



This may be true, but the anecdotal experience that convinced me to change from 15W40 Delo 400 to 5W40 Delvac:
I needed urgently to start my Unimog at ~-22F without preheating (daughter with dead battery in the cold). The engine started, but a few seconds later the "STOP" dash light and buzzer came on, indicating insufficient oil pressure after a prescribed interval. I waited a couple of minutes, restarted, carefully monitored pressure using the digital readout on my dash menu. Pressure very slowly ascended from the critical 7 psi cutoff to 40-50 psi over several minutes, then I proceeded.
Maybe no actual damage, but scary.

Charlie
 
Similar experience with starting a Land Rover in -30F conditions with 20W50... it was 25 years ago... and it was my first (and last) winter there. I had just moved there from California. Rocker arms SQUEAKED for 5 minutes until oil got up there. Zero oil pressure for the first two minutes. Next obstacle was the straight 90 gear oil in the diffs and gearboxes. The old Land Rover wouldn't move. I had to start in low range. A winter of object lessons, it was.
 
Originally Posted By: m37charlie
Originally Posted By: dnewton3
Interesting to note something here: What you "hear" turns into what your mind interprets. You believed that the 15w-40 Delvac was causing the engine to strain at start up (for a lack of a better term), right? And yet the wear results show no increase in wear issues whatsoever. The 15w-40 is rated as "preferred" by GM down to zero deg F. My point is that many people fear engine damage from thicker fluids in winter, but much more often than not, there is never any damage that materializes. The "fear" people have is all imagined; it rarely if ever manifests into reality.



This may be true, but the anecdotal experience that convinced me to change from 15W40 Delo 400 to 5W40 Delvac:
I needed urgently to start my Unimog at ~-22F without preheating (daughter with dead battery in the cold). The engine started, but a few seconds later the "STOP" dash light and buzzer came on, indicating insufficient oil pressure after a prescribed interval. I waited a couple of minutes, restarted, carefully monitored pressure using the digital readout on my dash menu. Pressure very slowly ascended from the critical 7 psi cutoff to 40-50 psi over several minutes, then I proceeded.
Maybe no actual damage, but scary.

Charlie


Your experience is certainly valid; can't take that away from you.

I would simply note that there are many differences in the goals/objectives of using an HDEO, and how to judge the results.

It was my impression that the OP was concerned about wear at start up (although his description was certainly a bit vague). My point is that wear (itself) really does not seem to be affected nearly as much as folks would believe, according to all the UOA evidence we see here.

But there are other reaons to use a thinner fluid ...
In your specific example, the "benefit" to using a full syn over a dino 15w-40 isn't so much wear reduction, as it is starting ease and time-to-drive-cycle. The 15w-40 may protect as well in actual wear metal counts, but it cannot avert the "mental stress" factor and such. Further, as we all know, in ultra-cold temps, compression-ignition engines really need the speed of cranking to help assist the heating of the air charge during the actual compression stroke. Yes, intake air heaters and common rail injection help to a large degree. Thinner fluids help the crankshaft spin faster, when means more heat in the compression event. Thinner fluids also pump easier; very true.


The OP switched to T5 10w-30 from 15w-40 dino. There really isn't going to be a tangible wear reduction he's going to see. When we view the large macro-base UOA data, we see that generally a Dmax simply does not care what oil is in the crankcase in regard to wear, even in widely varied environments. (Presuming one is using a qualified HDEO ...). Now, he might see easier starting with the T5. He might see quicker pressure build-up with the T5. But he's not likely to see less wear from the brand/base stock/grade change he made.

In fact, this is precisely the reason I use dino 10w-30 Rotella in my Dmax. I get a bit quicker turn-over and pressure from the thinner oil, and yet it holds up just as well in the summer heavy-tow cycles I put it through. If I lived in an even colder area, I likely would consider T5. But I don't "need" T5 where I'm at.

Side note:
I, too, once had older n/a IDI diesels; Ford 2.0L Escort and a 2.0L Tempo. Wow - what a starting challenge when it dropped below 20F. They only had one battery, and they struggled to turn the engine over with enough voracity. Sure, the glowplugs cycled, but that wasn't always enough. Those engines would have benefitted from thinner lube; not for wear protection, but for starting ease. Back then (in college) I didn't know anything but what the dealer told me; use Rotella 15w-40. So that's all I used. Back then (the mid-80's) I'm not even sure what alternatives might have even existed. I was "lube ignorant" back then.


Point being this:
in really uber-cold temps, wear reduction is not really the greatest concern. Just getting started, and seeing enough pressure to be able to drive away, is typically the greatest conern. Here, lighter grades lubes work well.
 
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There's an SAE article I have on my home computer which is unfortunately not attachable since it is copy protected. It pertains to camshaft wear in modern emission controlled diesels in cold starts with 5W40, 10W30 or 40 and 15W40. In particular, engines like mine with roller bearings actuated by camshaft lobes supplying injection pressure.
It is very clear from the tests done with pressure sensors throughout the inside of the engines in question (Cummins HD engines) that at moderate cold temperatures (-30C) it takes maybe 30-40 sec to get full lubrication with a 5W40 vs 90sec for a 15W40. I can give the actual reference later today.
And they showed that it made a demonstrable difference in wear on the camshaft lobes.

Charlie
 
And an actual example of "fear" turning into "reality", though the circumstances were extreme:
An acquaintance had a Super Cub and a 6 volt VW bug. He changed the SAE 50 aviation oil in the Cub (ashless = no ZDDP) every 50 hrs.
He then put it in the VW. He used jumper cables from his 12V pickup to crank the VW in -20F. Result: seized bearings.

Charlie
 
Good examples. Not applicable to a Dmax as per this thread.

Look at the UOAs in this post in the lead post. (And many other Dmax UOAs). The engines simply don't care what HDEO is used. It doesn't get THAT cold in the OPs area. The Delvac dino he's been using previously has shown stellar performance. The T5 is not likely to be much "better". (It's hard to be better with such low wear at 10k miles). The T5 certainly isn't likely to do worse, either. I just don't see it being "better" in regard to wear. But it might start a bit quicker and pressure up a bit sooner. That was my experience with the ligher grade; that's why I chose it.

The OP changed to T5 because he feared issues that are not materializing in reality. The 15w-40 was working quite well. More likely a simple function of the excellent Dmax lube design. The engine does not have a lube preference; it works well with any HDEO used.

But like I said, your examples are valid. Just goes to show how and why picking a lube isn't a "must always use this; never use that" for every situation. Always better to understand the unique operational situation one is in.
 
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Originally Posted By: dnewton3


Picking a lube isn't a "must always use this; never use that" for every situation. Always better to understand the unique operational situation one is in.


Words to live by! Another quotable moment for Dave Newton.
 
Originally Posted By: dnewton3
Good examples. Not applicable to a Dmax as per this thread.

Look at the UOAs in this post in the lead post. (And many other Dmax UOAs). The engines simply don't care what HDEO is used. It doesn't get THAT cold in the OPs area. The Delvac dino he's been using previously has shown stellar performance. The T5 is not likely to be much "better". (It's hard to be better with such low wear at 10k miles). The T5 certainly isn't likely to do worse, either. I just don't see it being "better" in regard to wear. But it might start a bit quicker and pressure up a bit sooner. That was my experience with the ligher grade; that's why I chose it.

The OP changed to T5 because he feared issues that are not materializing in reality. The 15w-40 was working quite well. More likely a simple function of the excellent Dmax lube design. The engine does not have a lube preference; it works well with any HDEO used.

But like I said, your examples are valid. Just goes to show how and why picking a lube isn't a "must always use this; never use that" for every situation. Always better to understand the unique operational situation one is in.


I was hunting in my area for the regular HDEO 10w-30, but couldn't find it. T5 was the closest. Although I may not see an appreciable gain with the T5, this current batch I plan to take to 15K miles with a check @ 10K.
 
T5 is an excellent product, and given it's ease of attainment (just about every W/M around) I can understand.

Dino 10w-30 is coming out of the closet slowly, so to speak. I've always got mine at Menards, but that is a regional hardware chain. I've also seen it at many farm supply stores such as Rural King. However, I saw Rotella 10w-30 dino on the shelf at an O'R auto parts in Alamosa, Co last summer. You can get dino 10w-30 at Walmart, but you have to order it (they actually have a SKU for it).

I think you'll find the T5 10w-30 an excellent compromise between stellar performance and price value.
 
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