Synthetic oil as fuel?

Selahdoor

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I changed the oil in the front diff. It's normal 80-90 weight stuff.

Saved the old oil. I'll let it settle. Then I'll use it as clean as I can, to add to the fuel tank a bit at a time, just to add some lubricity.

I'm about to change the oil in the rear now.

It is synthetic.

I am wondering if I can do the same with the synthetic? Or is there a problem?

I mean synthetic is an organic oil, right?

And our trucks will run on peanut oil. Or WVO. Which is an organic oil...
 

chris142

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The rotary Mazdas use engine oil to lube the apex seals. They specifically say not to use synthetic oil in them. I do not know how that would corrodinate to our antique diesels.

Wouldn't gear oil stink as a fuel?
 

quickster

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Yeah I have done the 2 stroke thing. It has sulpher in it to add lubricity. Unless they removed that too.
 

TNBrett

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Synthetic oils burn just fine. Typically fill fuel filters with ATF when I replace them, and the only ATF’s I keep around are all full synthetic. No problems at all. FWIW, I don’t do that on newer stuff with DPF/DEF systems.
 

ISPKI

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The rotary Mazdas use engine oil to lube the apex seals. They specifically say not to use synthetic oil in them. I do not know how that would corrodinate to our antique diesels.

Wouldn't gear oil stink as a fuel?
Would you actually notice or care about the smell? Our motors dont exactly smell nice to begin with ya know.

Synthetic oil is still oil, its just refined, distilled, and purified beyond conventional oil. In some cases, it is refined from different fossil fuels that allow for a cleaner base of refinement - Pennzoil is known for this I believe.

Its like comparing a big jar of M and Ms with all different colors, some being regular, some being peanut, vs a jar of all milk chocolate red M and Ms. They are all still M and Ms.
 

u2slow

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Heavier the oil, the more I dilute with diesel. I dose thicker in the summer, and/or when planning a longer highway trip. Conventional gear oil will burn stinky if you dose high. I don't use synth gear oil, so haven't tried it for fuel. Synth engine oil has been fine.

The sulfur thing.... It's not a lubricant. Its the refining process (that strips that last bit of sulfur) that damages the fuel's lubricity.
 

YJMike92

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I run my diesel's on a mix of 30% diesel fuel 70% synthetic oil and trans fluid. I have a good supply of waste motor oil and trans fluid. It does fine.
 

subway

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make sure you mix it outside the truck if you can. I made the mistake of adding some gear oil then filling the tanks. it did not mix enough and clogged my fuel lines with just gear oil. I had to manually purge everything out before I got it going again. Using the fuel rushing in the tank is not always the best way to run mixed concoctions.
 

Selahdoor

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Good point. Thank you.

Now I am thinking about using a small gas can to make up my own "mix" can. Some diesel kleen, some used gear oil, and some diesel.
 

subway

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you can then check viscosity by taking an old container drilling a standard hole in it and timing to see how long it takes to run out. You will not get a true viscosity but it can give you a good reference if you are in the ball park where your fuel pump will work. You could see how long a gallon of oil vs diesel vs gas or a mix of flows out to get a reference. then you could compare where flowing as fast as diesel is the gold standard to shoot for.

but I have generally found if you can pump it in the engine, the engine will burn it. Used motor oil, transmission fluid, hydraulic oil, ATF, power steering etc. The limit is pumping it, then if you get to heavy on the mix it can get hard to start cold. But if the engine is good and up to temp it will burn about anything flammable.
 

Selahdoor

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I'm talking about a way to add some lubricity, and to use up old oil, rather than just tossing it.

Something with the old oil, some diesel kleen, and some diesel, that I can just add a little bit each time I fill the tank.
 

subway

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I figured you were just using up some old oil you had from changes. I was just letting you know it should not be an issue. just dont dump a quart or two of gear oil in the tank and full up the rest with diesel! LOL
 
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