Rotella T6 turned into jelly

Been away from this thread for a while. My guess is coolant leak into oil via oil cooler, head gasket, or some other contact point. Definitely warrants an oil analysis.
 
Sorry for the late reply to this thread. I glanced through the replies and one guy was close. It’s fuel dilution from interrupting the DPF regeneration while using B20, or higher, biodiesel. Mercedes puts a booklet in every BlueTEC diesel that explains how this happens. They tell the owner it will ruin the engine and it’s not covered by the warranty.
Mercedes warns the owner to change the oil ASAP after using B20 biodiesel. For what it’s worth, Motul 300V is the only oil I’ve found that says it’s compatible with B20 and won’t jell like this did. I’ve not found any oil additive that claims it can prevent this.
Another problem is a number of States only sell B20. You can’t get B5 or normal diesel fuel. One small tip, #1 diesel fuel is never B20. At least for now. B20 clogs the fuel filter in freezing weather.
 
Sorry for the late reply to this thread. I glanced through the replies and one guy was close. It’s fuel dilution from interrupting the DPF regeneration while using B20, or higher, biodiesel. Mercedes puts a booklet in every BlueTEC diesel that explains how this happens. They tell the owner it will ruin the engine and it’s not covered by the warranty.
Mercedes warns the owner to change the oil ASAP after using B20 biodiesel. For what it’s worth, Motul 300V is the only oil I’ve found that says it’s compatible with B20 and won’t jell like this did. I’ve not found any oil additive that claims it can prevent this.
Another problem is a number of States only sell B20. You can’t get B5 or normal diesel fuel. One small tip, #1 diesel fuel is never B20. At least for now. B20 clogs the fuel filter in freezing weather.
Do you have this booklet? Can you post screen shots?

If B20 ruins everything then how can it be sold? Is it labeled only for use with non-DPF engines?
 
Do you have this booklet? Can you post screen shots?

If B20 ruins everything then how can it be sold? Is it labeled only for use with non-DPF engines?
It doesn't "ruin everything" and he didn't say that.
Modern Mercedes DI diesels with DPF are sensitive to anything higher than B5.
I ran a 1992 Mercedes on everything from B5 to B100 for a decade with no problem. It had indirect injection. I wouldn't put a drop in the Bluetec Mercedes I'm driving today.
Hyperbole and overreaction.
 
It doesn't "ruin everything" and he didn't say that.
Modern Mercedes DI diesels with DPF are sensitive to anything higher than B5.
I ran a 1992 Mercedes on everything from B5 to B100 for a decade with no problem. It had indirect injection. I wouldn't put a drop in the Bluetec Mercedes I'm driving today.
Hyperbole and overreaction.
Hmmmm:

It’s fuel dilution from interrupting the DPF regeneration while using B20, or higher, biodiesel. Mercedes puts a booklet in every BlueTEC diesel that explains how this happens. They tell the owner it will ruin the engine and it’s not covered by the warranty.

Perhaps your interpretation of “everything” isn’t quite correct relative to my reply…. I too have run plenty of B20 in my fleet of IDI diesels. But ruining the engine is more or less “everything”… ever price a long block for one of these?
 
Direct quote:
"If B20 ruins everything then how can it be sold? Is it labeled only for use with non-DPF engines?"
Done. out
Yeah. Apparently you missed my question about labeling - if it is labeled for non-DPF engines, even though you quoted me. Anyone with a courteous reply could either answer, or indicate what it’s not to be used for… labeling or not. It’s not a huge stretch to say, again labeling or not, that it’s not for DI or something else. Since the context above didn’t mention DI, but mentioned DPF, I queued in on that. Mercedes is far from the only diesel engine manufacturer, so the fact that the OP said that the brochure came with every bluetec in and of itself doesn’t mean much, even though those engines have specific technologies. Heck, the situation we’re talking about here is a vw.

I don’t know what got into your knickers, but you should consider settling down a bit. Everyone wants to learn and understand. I was actually asking for the primary source to understand better from the manufacturer. Fortunately others were courteous enough to provide a link instead of being a jerk about a few words.

Comprehension, courtesy, and just a little bit of thought about what someone is saying can go a very long way versus the kind of attitude you portray. “Hyperbole and overreaction” are poor interpretations of simple questions and comments associated with specific claims about ruined engines and manufacturer documents.
 
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Sorry for the late reply to this thread. I glanced through the replies and one guy was close. It’s fuel dilution from interrupting the DPF regeneration while using B20, or higher, biodiesel. Mercedes puts a booklet in every BlueTEC diesel that explains how this happens. They tell the owner it will ruin the engine and it’s not covered by the warranty.
Mercedes warns the owner to change the oil ASAP after using B20 biodiesel. For what it’s worth, Motul 300V is the only oil I’ve found that says it’s compatible with B20 and won’t jell like this did. I’ve not found any oil additive that claims it can prevent this.
Another problem is a number of States only sell B20. You can’t get B5 or normal diesel fuel. One small tip, #1 diesel fuel is never B20. At least for now. B20 clogs the fuel filter in freezing weather.

If B20 is bad our entire state (MN) is screwed as we have a B20 mandate for the summer months since May 2018, you wouldn't think there would be a diesel left running in the state.........

 
If B20 is bad our entire state (MN) is screwed as we have a B20 mandate for the summer months since May 2018, you wouldn't think there would be a diesel left running in the state.........

That was kind of my point. If B20 is such an issue that engine damage can occur, and if no options or alternatives exist, that’s a pretty significant issue. Regardless of how people want to interpret anyones’ comments.
 
Seems to me that the issue can be attributed to some specific situations, ie engines with DPF systems ....... and probably only a subset of those have DPF control and regen programming that will put them "at risk" to fuel contamination of the oil. Maybe I am not looking at it correctly, but to me this thread is just an alert that raises my awareness!
 
Something I found odd was the first pic in the original post. He is holding up this mass of goo, and the hand holding that mass is clean, right down to the fingertips that are gripping the stuff.
 
Something I found odd was the first pic in the original post. He is holding up this mass of goo, and the hand holding that mass is clean, right down to the fingertips that are gripping the stuff.
I agree, I call BS on the post. The only time I ever saw oil get even close was at the dealership a woman hadn't changed her oil for 110, 000 miles and it wouldn't drain from the sludge. The supposed oil in the pictures was way too clean.
 
If you’re using B20 or above you should really cut the oil changes in half, not stick to the recommended service intervals. Manuals will usually say something about oil change intervals if using b20 or more..

My ram has a recommended oil change interval of nothing more than 15,000 miles (my manual doesn’t have a set mileage interval, only that it shouldn’t exceed 15k miles) but I change my oil every 3-4k miles.

I might extend it with full Synthetic 5w-40 now that I am running it.

Oil changes and air filters are cheap, engines and turbochargers aren’t.
 
Biodiesel in general will affect diesel engines

Biocrap has an affinity towards water and it will over time dilute the oil
 
Hey guys, my father has a 2013 TDI golf with approx 324000km(201324 miles). Oil used in the car is Rotella T6 and oil changes have been completed every time the counter in the car indicates the vehicle is due. Recently he ran into a no start situation which was diagnosed as a clogged DPF by VW. The DPF was changed under warranty at the dealer and when the tech started the car he claimed that the oil light came on so he checked the oil and found it was down roughy 2 quarts. Tech decided it would be better to just change the oil completely. So tech pulls the oil plug and oil leaves the pan very slowly, and is stating he believes the engine is heavily sludged up and wants to pull the oil pan for further inspection. It’s at this point that I instruct my Dad to have the car towed to my place as this wasn’t adding up, I performed the last oil change on the car and noticed no issue at all with the oil draining. So car comes to my place and I pull the oil pan off and find massive amounts of this jelly sludge. It has a rubbery texture and breaks apart fairly easily in your hands. I was able to clean out the oil pan fairly easily as it doesn’t appear to stick to aluminum very well, the windage tray and oil pickup(plastic) however is a different story. I’m currently soaking these parts in varsol, which has helped with loosening the deposits however deposits do no appear to be dissolving, rather it looks like a bunch of permatex silicon floating around in the varsol. In doing some google searches I saw that coolant in the oil can cause this sort of thing, however we haven’t had to add any coolant to the car. Car had some front end work completed a couple of months ago, I’m concerned someone may have sabotaged his engine figuring him has an easy target(he’s 80 years old) . Would love any and all feedback!! Thanks!!
I’m trying to give up gambling for the new year, but I would bet that if you look at most of the used oil analysis for diesel engines-the most stellar and pristine oil analysis are some cars or trucks that have the emissions deleted or heavily modified… I remember MolaKule posted an article about a new mission strategy for diesel engines which would help them run cleaner without all the draconian emission systems like the diesel particulate filter… in my experience looking at analysis on Bob is the oil guy. I would blame the engine in combination with the emissions design with regards to Schlage or pour oil analysis as opposed to the oil itself.
 
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