[gmcvt]

Originally Posted by DaveC113

Water in oil from not getting it hot enough frequently enough... gotta drive it like you stole it on a frequent basis!

[gmcvt]

DRIVEN OIL was kind enough to respond:

Hello and thanks for your email!



I agree with Blackstone, the reported TBN is at the low range. Based on the amount of calcium present in the used oil analysis you were at the point of needing to change the oil, which appears to be 5,000 miles.



I noticed in your email you mention that you have been running E-85 but the Blackstone report has Unleaded Gasoline. I would suspect the acidic condition that has depleted the TBN of the oil may be based on the use of e85. The oil did not go acidic per say, however it was exposed to high levels of more acidic by-products probably from running E85. That’s one of the things we may encounter with biofuels in general. In actuality the TBN did it’s job – but the 5,000 mile interval was the true maximum point of effectiveness. I was surprised as well but we need another sample to establish any sort of trend. The viscosity is good and the fuel dilution looks OK as well – so I would really like to see the next sample.



Based on the wear metals I would suggest a shorter interval for your next oil change. This will get some of the particulates out of the engine and you will be past the wear in phase. We can then look at the TBN retention sooner in your drain interval (without the wear contamination).



Thanks! Please send me a copy of the next sample so we can continue.

[gmcvt]

If what Driven said is true regarding E85, then I'm not sure I understand why that I ran E85 in my 5.0 with their oil and didn't have a problem.

[cmitchell17]

Originally Posted by gmcvt

If what Driven said is true regarding E85, then I'm not sure I understand why that I ran E85 in my 5.0 with their oil and didn't have a problem.

I run E85 100% of the time I have been since about 30 or 40k and I'm at almost 100k now. My iron spiked up to 55 with my first analysis after I installed my cam and heads, I just sent my last oil sample out so we will see if the levels are increasing or not. Before my cam my iron and wear metals were very low and I still was running E85.

[gmcvt]

Originally Posted by cmitchell17

I run E85 100% of the time I have been since about 30 or 40k and I'm at almost 100k now. My iron spiked up to 55 with my first analysis after I installed my cam and heads, I just sent my last oil sample out so we will see if the levels are increasing or not. Before my cam my iron and wear metals were very low and I still was running E85.

Yah, that answer doesn't make sense to me. I mean, I guess there is a scenario where that might be possible but I dont pretend to know what that would be.

[Gunkk]

Originally Posted by gmcvt

I do run E85 exclusively and my catch can is always full of a homologation of something between what appears to be milky oil and possibly some corn.

Ahhh E85. That's it. Burning alcohol can make acids. So this is almost certainly the culprit here. You will have to change oil more frequently. I recommend changing the oil when the OLM says 50% or 3k miles, whichever comes first. Keep doing the TBN analysis and let that be your guide. Winter will be worse than summer.

Your catch can will fill with water and light hydrocarbon condensates very quickly in the winter (like weekly if your trips are frequent and short). E85 adds to this. Chocolate milk shake appearance is normal in the winter. Will be darker in the summer as higher temps cause water to evaporate/burn off. Analysis shows no water in the oil so your CC is doing its job.

[gmcvt]

Originally Posted by Gunkk

Ahhh E85. That's it. Burning alcohol can make acids. So this is almost certainly the culprit here. You will have to change oil more frequently. I recommend changing the oil when the OLM says 50% or 3k miles, whichever comes first. Keep doing the TBN analysis and let that be your guide. Winter will be worse than summer.

Your catch can will fill with water and light hydrocarbon condensates very quickly in the winter (like weekly if your trips are frequent and short). E85 adds to this. Chocolate milk shake appearance is normal in the winter. Will be darker in the summer as higher temps cause water to evaporate/burn off. Analysis shows no water in the oil so your CC is doing its job.

Not really sure I need Black Stone with you (and others) around. Thank you!

Again though, its odd that I did not have this issue with my 5.0. And my drive cycles were the same, Driven oil and same change interval.