Amsoil 10w-40 2.7k miles; 2015 dmax 125k miles

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Very long time reader and first time poster on this board. Figured I would post my first UOA results. Thinking I will use a different lab next time because of the vagueness of the report. They found possible coolant intrusion, but I've had no coolant consumption in over 4k miles so I'm not sure what else could elevate the potassium levels, which led me to post here. Let me know if any of you guys have any input and thank you for the years of help I've gained from this board!
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Very long time reader and first time poster on this board. Figured I would post my first UOA results. Thinking I will use a different lab next time because of the vagueness of the report. They found possible coolant intrusion, but I've had no coolant consumption in over 4k miles so I'm not sure what else could elevate the potassium levels, which led me to post here. Let me know if any of you guys have any input and thank you for the years of help I've gained from this board!
Can we get a backstory on that coolant consumption? 4K miles is pretty recent in "Oil Change Interval" time. Could be just residual coolant floating in there. It may take multiple oil changes to get all the coolant out of the crankcase. Or it may indicate that issue still persists.
 
Is this the 6.6L Dmax? or a little Dmax?

The Fe and Si are quite high for only 2.7k miles. Those have the potential to be related; check for an intake tract leak.

As for the coolant, sometimes the leaks can be difficult to discern at the bottle so they are hard to detect.

What can you tell us of the history of the engine? Is it modded (tuned)?

Are you using any oil additives? If so, which?



I'd recommend two things:
- get a VOA on the oil so you understand the starting numbers
- get another UOA to confirm or contradict this one
 
Morning fellas, I apologize for not being more clear. The truck has never used any coolant and the reason for new coolant was 4k ago when I replaced the cooling stack. This is the first uoa I've had done on the truck as it's over 100k now and time to monitor it. Truck is heavily tuned, egr and dpf full delete. No oil additives, I do use stanadyne performance additive in the tank to try and keep the cp4 happy. This oil did in fact have very low miles, but every one of those miles was very hard use towing my fifth wheel across half the country (22k loaded) and playing in the sand more than a few times. I also tend to have a very heavy foot. I will get a VOA and after about 3k I will change the oil again and do another UOA.
 
Is this the 6.6L Dmax? or a little Dmax?

The Fe and Si are quite high for only 2.7k miles. Those have the potential to be related; check for an intake tract leak.

As for the coolant, sometimes the leaks can be difficult to discern at the bottle so they are hard to detect.

What can you tell us of the history of the engine? Is it modded (tuned)?

Are you using any oil additives? If so, which?



I'd recommend two things:
- get a VOA on the oil so you understand the starting numbers
- get another UOA to confirm or contradict this one
@dnewton3, Here is a VOA and it kind of contradicts my UOA in my eyes... How could the TBN, additives and everything there be lower on brand new oil?? This was straight from the jug and zero contamination. I will be getting another analysis of my oil in about another 1500 miles, but I again think I need to use another lab because of the contradiction in results. I've also been running this oil well over 15k miles and 5 plus change intervals so there shouldn't be residual additives from other oils left.

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I think it's possible they got your used sample mixed up with another person.
The Ca, Zn and Mg are key give aways; not anywhere what we'd expect them to be one relative to the other.

The TBN is off a tad, but that's probably close enough to be just a measurement error.
 
I think it's possible they got your used sample mixed up with another person.
The Ca, Zn and Mg are key give aways; not anywhere what we'd expect them to be one relative to the other.

The TBN is off a tad, but that's probably close enough to be just a measurement error.
That's pretty sad since it gives me no faith in the first sample... Can anyone recommend the best lab for testing? Cost is really not an option I'm worried about.
 
Generally Wix lab results are not bad, and the cost is decent. Samples have been known to get swapped by accident at the other prominent labs; it's not unique to Wix. Blackstone certainly has done it; so has Polaris. My point is that you can consider using other lab(s), but that's not going to eliminate the risk of a swapped sample.

I cannot assure you that it got swapped, but it just seems so given the odd additive results. How does it make sense that Ca went down nearly 500ppm in only 2700 miles, but Mg went UP by around 650ppm? Zn and moly also go up after use??? If, as you state, you've been using this same oil brand/grade for the last several OCIs, then we can only conclude one of three things, either ...
- Amsoil has terrible control over their additive package dispersement in blending (this, I highly doubt)
- Wix equipment calibration went off the reservation somewhere between those two oil analysis' (possible, but not probable as most labs are good about taking care of their equipment)
- Wix got a sample mixed up with someone else's (this is far more common and likely because this is a result of human error)
See if you can call the lab directly and speak with them about the results.


I see that Amsoil only has one product in their diesel 10w-40 vis, so it's the AMO you're using here? Perhaps also call them and ask what the VOA results should be.
Here is a VOA from AMO from almost 11 years ago ...
Here is a UOA (gas application but using AMO) from 8 years ago ...
As you can see, those both have a huge load of Ca and almost no Mg.
There's a pretty big difference between that and the results you got.
Maybe Amsoil has changed the formulation in the last few years? I would think so, given that the older VOA was CI-4+ and UOA was probably CJ-4.
I don't see any more recent VOAs or UOAs for reference, so perhaps calling them is the best approach.
 
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