Hey Y'all,

Last week I stopped at a new gas station that had a good price on Diesel (under $4/gal) and proceeded to fill the tank. It was only as I left to go pay that I notice in fine print on the pump (BioDiesel may contain 5 - 20% biodiesel blend). I asked the attendant what percentage they were running and of course he had not idea. So far the tank has run fine with no real change in MPG except that I have had two regens run on this tank which is unusual for me. No real change in driving habits or routes so the two regens is unusual. Anyway - my question is whether this is normal with B20 or something I need to worry about. Thanks

 

Your truck is rated to handle B20, I wouldn't worry too much. I do think it's kinda strange though... logically, B20 should produce *less* soot, therefore need fewer regens. Maybe the EGTs are lower on B20, meaning it actually needs more active regens? I dunno.

I do like that you're seeing equivalent MPG! I've always wondered if B20 would drop enough in energy content to be noticeable. I'm sure it has a lot to do with the quality of bio that's mixed in. some is terrible, some is awesome, and everything else is in between somewhere. Maybe you got some of the awesome stuff

 

Interesting thought on the lower EGTs, I had not considered that. I was pleased with the MPG on the tank. I averaged around 18 for the tank which is above my long-term average using the same duty cycle. I did add my usual additive (SlickDiesel) in the usual ratio so maybe that helped as well. I suspect that the future lies in more biodiesel at the pumps once the military switiches to bio-blend as standard and the US Gov figures out that subsidizing biodiesel makes loads more sense than ethenol. I would guess five years max and we will be seeing BXX adverstised as the lower cost alternative to straight-up dino fuel at the pump so perhaps this this just something to keep an eye out for.

 

I think that the quality of bio blends are still suspect. I'd continue to use cetane boosting additives. Wouldn't suprise me that it was behind the "northerner" troubles.

 

I would also run a cetane booster to help you get thru that tank of garbage. Might want to drain your fuel/water separator to ensure no water.

 

I don't care if my truck says it will run B20, I stay as far away as I can from a diesel pump that has that letter on it.
I don't have specific facts but simply my decision.
As I continue to read these posts, it seems that's harder to do in the northern states than the southern states.

Biodiesel I thought was more expensive and has around 11% less energy so you burn more biodiesel than you would dyno diesel or whatever it's called (petroleum diesel?).
This will drop your MPG.

I am confused about the regen's though.
You would think the fuel would be a little cleaner.
Isn't the combustion process improved with bio-diesel with slightly higher levels of oxygen?
That would mean higher temps creating more NOx and using more reductant (DEF).
I'm not saying I'm right, just asking to create a discussion for someone who does know.

Regardless, I don't understand how it's worth it.
These trucks are capturing the soot with the DPF and reducing NOx with the DEF system.


EDIT: I may have contradicted myself by saying it's less efficient but burns at a higher temp.
Oh well, we'll see what others say. I might learn something before the day is over.

 

I have nothing to add except that bio isn't *necessarily* garbage. It's just in dire need of regulation, so there is a lot of garbage out there on the market. The way I understand it though, good biodiesel won't hurt these trucks at all. With the right additives (just like with petro-diesel), we could run B100 without any adverse effects (other than higher DEF usage and possibly a voided warranty). The problem is finding B100 that's worth a crap.

FWIW, one of the best additives you can put in petro-diesel is.... drumroll please... biodiesel. There was a study (the results of which are posted somewhere on FTE) that compared all the major additives. Biodiesel of high quality was rated among the best for lubricity and cetane. Still, we have the quality control issues... so it's really just theorycraft at this point.

 

I have 1,600 miles on mine and never seen a regen. How can you tell?

 

Active Regeneration is indicated by a productivity-screen message that says "Cleaning Exhaust Filter". This message is orange and I think I have noticed all of them in my truck... but many people here say that they miss them. I've probably missed some, too . The message only stays up for 2 or 3 seconds, then disappears. You may also notice a distinct smell, a bit like burning rubber mixed with hot brakes. you will almost certainly notice a drop in instant MPG. It may or may not affect your average MPG, that depends on how long your running total has been going.

I don't know how/if the non-LCD models indicate an active regen, unfortunately.

 

Thanks for the thought provoking discussion. I was pleasantly suprised that my MPG did not take a hit and given that two active regen cycles occured during the tank means that it actually gave better than average running MPGs. The two regens might have just been a fluke of timing. As I mentioned the price on the Bio was $.10 per gal cheaper than the station down the road but this might have just been timing of deliveries rather than a lower cost product. All-in-all I was satisfied and would not actively avoid bio-blend if offered at a competitive price at a high volume retailer. Like I said in a previous post, I suspect that within 5 years bio-blend may be a reasonable option and may be mandated in some areas... Maybe not necessarily a bad thing for our wallet, our energy independence, and the environment if our government can get it right.

 

I know I have missed a few of them. Most of the time I can tell is by the instant fuel mileage indicator reading a lot lower (usually in the 11 mpg range at highway speeds) and by that smell djjoshaud mentioned (nost noticeable at lower speeds).

 

Sorry, on the original topic. Just like any other fuel, it is only as good as who is producing it. I know there is standard methodology for testing it (ASTM D6751) and somewhere around 500 million gallons are made each year.

I wouldn't be too worried about using it.

 

I burnt a tank of that "garbage" B20 going through IL and IN with my trailer last winter. I averaged a full 10% better fuel economy with that stuff; the truck didn't seem to mind it one little bit.

In my last job as a professional truck driver I burned thousands of gallons of the stuff, as that's all that is available at certain chain truckstops in some parts of the country. Never hurt a thing.

Now I certainly wouldn't seek out B20 when looking for fuel, as I still think dino fuel is a bit easier on the engine. But biodiesel is NOT some high-school science project that's being foisted on our trucks without the proper research. This is a proven fuel, and just like regular diesel you can have great quality or poor quality.

 

Interesting discussion. Wonder if the emissions on the 6.7 vs the 6.4 make it better with the bio?

I know with mine (6.4) it just does not like bio. Other 6.4 owners experienced negative results as well.

 

And we all better get used to living with it... With fuel prices going over $4/gallon in my area, the alternate fuel debates will begin again. And as Crazy says, it's being used today. I think the bad rap it gets is that when it is used, especially if the vehicle has been running pure fossil, is it has a tendency to act a bit like a solvent and loosen crap from the tank and lines left by the fossil -- which then makes it look like the bio part is causing the problem.

I would run more of it, if it was available readily in my area. I think the processing plants tend to be more in the areas where the fuel is grown (soybeans, etc.). I'm sure transportation cost of getting it to the refineries is a part of the reason it is not seen uniformly around the country.