2021 Chevy Duramax L5P - 15,450 miles/387 hours on oil - 37,000 total miles/882 total hours - HPL 5w-40

wwillson

Staff member
Joined
Aug 20, 2003
Messages
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Location
Colorado
This is my 2021 Chevy 3500 DRW L5P Duramax that pulls a 20,000 pound 5th wheel for a combined GVW of 29,500 pounds. I'm still pulling in eighth gear and oil consumption continues to be very low, but not zero. There have been two oil filter changes so far in the OCI, which combined required about 1 quart of oil to bring the level to full. The engine has consumed about 1 quart of oil so far in this 15,450 mile OCI. There has been 2 quarts make-up oil added. We pulled a couple thousand miles into a headwind and in hilly terrain. If you don't want to be "that guy" going 50 MPH on the interstate, then you have to keep your speed up and take the EGTs you get. I did see grade pulls with EGTs as high as 1,350°F for a couple minutes. This OCI sees Fe at 4.2ppm/1k miles vs. 4.6ppm FE/1k miles in the last sample. Silicon increased by 6ppm in over the last OCI, which tells me the air filter is performing well, even though we were in a dusty environment for part of this OCI. TBN retention is very good with a TBN of 12.86 after 15,450 miles and nine months use. The viscosity is virtually the same as brand new oil, this oil doesn't shear.

This oil is in great shape and will be sampled again at 20,000 miles.

Sample Information
Sample Date6/23/202107/17/20218/24/20214/4/20227/1/20228/10/20221/18/20234/17/2023
Machine Age miles2,5002,7008,90016,00021,50021,55031,30037,000
Oil Age miles2,5002006,40013,50019,000509,75015,450
Machine Time hours5562214350495496734882
Oil Time hours5571522954401239387
Filter Age miles2,5002006,4007,1004,000505,0009,800
Oil ChangedYesNoNoNoYesNoNoNo
Filter ChangedYesNoYesYesYesNoYesYes
Make-up oil0001.5 qts2.5011
BrandFactoryHPLHPLHPLHPLHPLHPLHPL
Viscosity15w-405w-40 CK-45w-40 CK-45w-40 CK-45w-40 CK-45w-40 CK-45w-40 CK-45w-40 CK-4
Wear Metals
Iron1243667102166185
ChromiumTD]
[TD]TD]
[TD]2
34TD]
[TD]2
2
NickelTD]
[TD]0
0TD]
[TD]0
TD]
[TD]TD]
[TD]TD]
TitaniumTD]
[TD]TD]
[TD]TD]
[TD]TD]
[TD]TD]
[TD]0
TD]
[TD]0
Silver3TD]
[TD]TD]
[TD]TD]
[TD]TD]
[TD]TD]
[TD]TD]
[TD]TD]
AluminumTD]
[TD]0
151314389
Lead61243120
Copper109288518820329185197
Tin61066222
VanandiumTD]
[TD]0
0TD]
[TD]TD]
[TD]TD]
[TD]TD]
[TD]0
Additives
Boron120151221631417
BariumTD]
[TD]0
000040
Molybdenum2514450504537541469574
ManganeseTD]
[TD]TD]
[TD]TD]
[TD]1
2TD]
[TD]2
2
Magnesium67299596810089249138311001
Calcium12602439241425572459237521112722
Phosphorus1000109910291064981973847968
Zinc11551179114812851233115910781292
Contaminants
Silicon8733484654182127
Sodium75335258
Potassium11243555961621
Fuel %TD]
[TD]TD]
[TD]TD]
[TD]TD]
[TD]TD]
[TD]TD]
[TD]TD]
[TD]TD]
GlycolNEGNEGNEGNEGNEGNEGNEGNEG
Soot%0.10.10.40.60.80.20.60.7
Fluid Condition
TBN8.5514.913.313.710.813.913.7612.86
Viscosity13.914.513.814.9714.514.414.514.5
[TD]
[TD]
[TD]
 
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Just an observation. When I look at your first 50 mile sample on this run of oil it accumulated 16 ppm iron so assuming we just say that is from left over from previous run I get 4.466 PPM when subtracting 16 1st - 85 2nd = 69 PPM / 15,450 = 4.466 PPM over this whole run so far. I know its best to look at each sample individually which is what you're doing.

Also look at the J shape of the additive package. High, low, then Higher. Anyone have an explanation for additives having babies?
 
Just an observation. When I look at your first 50 mile sample on this run of oil it accumulated 16 ppm iron so assuming we just say that is from left over from previous run I get 4.46601941748 PPM when subtracting 16 1st - 85 2nd = 69 PPM / 15,450 = 4.46601941748 PPM over this whole run so far. I know its best to look at each sample individually which is what you're doing.

Also look at the J shape of the additive package. High, low, then Higher. Anyone have an explanation for additives having babies?
Because when the oil evaporates the additives are left behind and get more concentrated.
 
Shouldn’t you be also testing for oxidation? TBN alone shouldn’t be used as a condemnation data point if you are trying to prove something by pushing it this far.
 
Shouldn’t you be also testing for oxidation? TBN alone shouldn’t be used as a condemnation data point if you are trying to prove something by pushing it this far.
Since HPL's base oils are high in carbonyl groups, ASTM D7414 will show high oxidation even in virgin oil. I looked back at the previous UOAs from this run and the oxidation values were:

50 miles 40.6
10,000 miles 43.1
15,500 miles 44.1

The increase in oxidation value was 3.5. Is it fair to say at 15,500 miles the oxidation of his oil is 3.5? I don't know, but our chemists here should have an idea. Wearcheck's oxidation limit is >25. If my swag at oxidation is valid, then this oil has little oxidation and good for continued use. I have seen the PDSC data on this oil in the lab and I can assure you it has very high oxidative stability.

However, do we really need the oxidative stability test when the viscosity, TBN, and wear numbers are all good?
 
Since HPL's base oils are high in carbonyl groups, ASTM D7414 will show high oxidation even in virgin oil. I looked back at the previous UOAs from this run and the oxidation values were:

50 miles 40.6
10,000 miles 43.1
15,500 miles 44.1

The increase in oxidation value was 3.5. Is it fair to say at 15,500 miles the oxidation of his oil is 3.5? I don't know, but our chemists here should have an idea. Wearcheck's oxidation limit is >25. If my swag at oxidation is valid, then this oil has little oxidation and is good for continued use. I have seen the PDSC data on this oil in the lab and I can assure you it has very high oxidative stability.

However, do we really need the oxidative stability test when the viscosity, TBN, and wear numbers are all good?
I think that is correct. You had a baseline oxidation value at 50 miles & then ending value at 15.5k. Subtract one from the other like you did to get 3.5.

Wearcheck's limit is probably 25 over the virgin sample. I've heard of labs going up to 30 above VOS. You're well within spec on this oil.

I saw a post from HPL saying they couldn't believe they really liked the CK-4 version but didn't think they would like it up until about 2 weeks prior. I'm sure one of the important aspects they were referring to is oxidation stability in CK-4 vs CJ-4. But this is no inside secret CK-4 Does better in that area.

Oxidation is an important read, It's a piece to the puzzle when looking at the viscosity & also soot levels. It provides more evidence & we all like to see more of that if we can. I would argue for getting oxidation sampled when running longer ODI. Let say you have a high soot reading. Did the high soot cause the oil to thicken? It is a good measurement.
 
hey Wilson, it's interesting how the oil holds up... have you ever figured out the break even point on oil cost versus conventional oil/filter on the factory schedule?.

way I look at it you have the cost of the HPL oil twice, plus 4 make up quarts, plus 8 samples and 6 oil filters over a 2 year period..

for comparison wouldn't you be looking at 4 conventional oil changes over what amounts to a 2 year period. the mileage is too low to be much of a factor. I can do my Cummins 6.7 for less than 50 bucks.. just throwing that out there for comparison.
 
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Since HPL's base oils are high in carbonyl groups, ASTM D7414 will show high oxidation even in virgin oil. I looked back at the previous UOAs from this run and the oxidation values were:

50 miles 40.6
10,000 miles 43.1
15,500 miles 44.1

The increase in oxidation value was 3.5. Is it fair to say at 15,500 miles the oxidation of his oil is 3.5? I don't know, but our chemists here should have an idea. Wearcheck's oxidation limit is >25. If my swag at oxidation is valid, then this oil has little oxidation and good for continued use. I have seen the PDSC data on this oil in the lab and I can assure you it has very high oxidative stability.

However, do we really need the oxidative stability test when the viscosity, TBN, and wear numbers are all good?


This….
 
Do wear metals in suspension contribute to additional wear on the engine's internals? I suppose the oil filter isn't "catching" all the particles and therefore are detected in analyses.
 
Do wear metals in suspension contribute to additional wear on the engine's internals? I suppose the oil filter isn't "catching" all the particles and therefore are detected in analyses.
They "can" and will eventually but it's a tipping point during the oil run. Check out @dnewton3 post about oil analysis & wear rates. It is valuable information that can shead light on how to decipher UOA and watch out for wear caused by dirty oil. Essentially oil can hold a certain amount of oil and once it starts degrading it may start contributing to wear.

Standard Deviation info although I'll admit I don't know how to compute such measurements yet.

The idea is to learn when that wear starts and schedule to change it before that happens for all future oil changes.
 
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Do wear metals in suspension contribute to additional wear on the engine's internals? I suppose the oil filter isn't "catching" all the particles and therefore are detected in analyses.
Yes the metals in suspension can cause wear. However, none of the metals appearing on an analysis contribute to wear. The particles that cause wear are not visible to a spectrographic analysis unless some sort of pre-processing is performed on the sample such as an acid digestion. ICP measures elements in solution not particles. "Wear particles" are far too large to register on a UOA and are in fact filtered out of the sample to protect the instrument.
 
When I perform a used oil analysis at oil change, I sometimes take 2 samples of the oil. The first sample goes straight in the clear container and off to the lab. The 2nd sample, I slowly pour through double layered coffee filters. Coffee filters are ~98% efficient @ 2 um and ~50% @ 0.3 um. Sometimes I'll find some very small debris in the coffee filters. I then do a magnet test on those particles to see if they're ferrous or not. I once sent both samples to the lab, one unfiltered and one filtered by coffee filters, and the ICP returned the same element numbers across the board within a margin of error except for boron.
 
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