Biodiesel in the mix and MPG drop

racertracer · **Posted:** Fri Jun 11, 2010 11:44 pm

I have been filling up on biodiesel for the past 8 fillups and I have noticed a significant decrease in MPG.

The following data will depict typical MPG using different grades of Biodiesel versus Ultra Low Sulfur diesel (ULSD) in my 2005 Jeep liberty CRD over the past 2 1/2 months and 8 fillups, with the GDE tune.

ULSD = 25 in town / 29 highway / At the Local Shell filling station.

B20 = 22 / 24 One fill up

B50 = 21.5 / 22 Two fill ups

B100 = 18.5 / 20.5 Five fill ups

Has anyone else made any these observation?

10000degrees · **Joined:** Thu Apr 08, 2010 7:14 pm **Posts:** 30

I have ran every blend from b2 on up to b100 in a 86 ford escort (mazda diesel,) 96 e300 mercedes and a 2007 dodge ram. seemed that the ram had the worst drop off of the three. I thought it would be the other way around 'cause the ram had a turbo. the escort and mercedes were normally aspirated. I would guess that your results are about typical, if not a little low. power was noticeably lower in the merc and the escort, but little to no difference in the ram. I haven't tried it in my libby yet, only had it for a few months and haven't made any fuel for a while. I would definitely make the recommendation that you buy your fuel from a reputable dealer or filter the heck out of it. I used a ONE MICRON ABSOLUTE type filter on my stuff for CR type diesels. can give you more info if you would like. oh yeah, beware, dogs may chase you due to the scent of your exhaust! :BANANA:

stoutdog · **Posted:** Sat Jun 12, 2010 2:32 am

Your drop is a little steeper than I've experienced, but a drop of some degree is to be expected. I lost about 1-2 mpg running B25 and 3-4 mpg running B80-100.

racertracer · **Posted:** Sat Jun 12, 2010 6:25 am

I get my supply directly from the truck pump at TriState biodiesel in NYC, a reputable supplier. The biodiesel production manager at TriState informed me that a drop in MPG is normal when using biodiesel and that many local filling stations supplement their Ultra Low Sulfur Diesel with biodiesel to take advantage of the lower cost and reselling the mixed fuel to customers at a profit. He mentioned that the greatest benefit to a driver using biodiesel is not cost but rather a reduction in engine wear. Biodiesel substantially increases engine life by 1/2 and benefits the environment by decreasing our need for foreign oil.

So if what the manager said is true, and our engine is rated at 200,000 miles or more, can we expect an increase of 400,000 miles or more in our CRD when using biodiesel?

Also, could this be the reason why we experience a drop in MPG figures when we fill up at various diesel fueling station?

mikey1273 · **Posted:** Sat Jun 12, 2010 9:04 am

I have played with bio too and I started with about B50 I noticed a difference in MPG. I can't remember the numbers but it was a few less. with lower blends I didn't notice it much. the good things I did notice was less combustion noise, smoother idle, and the engine felt just a little more powerful.

AZ CRD · **Posted:** Sat Jun 12, 2010 10:05 am

bio has fewer btu's per gallon

CRDMiller · **Posted:** Sat Jun 12, 2010 4:03 pm

Az crd is correct.

Code:

                    
                      ASTM d2  ASTM b-100
BTU/gal             140,000   118,000
Specific gravity      0.85       0.88
Density/gal @ 15c     7.079     7.338
Carbon by weight       87%        77%
Hydrogen by weight    13%        12%
Oxygen by weight       0%          13%
Flash Point             60-80c     100-170c
Cetane                   40-55     48-60
pour point           -35 to -15c   -15 to 16c

These are averages of astm spec fuel d6751 and astm 975 (current b-100 spec and 2002 d2 spec)

boilermaker2 · **Posted:** Tue Jun 15, 2010 10:00 pm

I wouldn't go out of my way, but if it is time to change the fuel filter I would not skip it. BD is a great emulsifier (cleaning agent). If you had any gunk in your tank from the dyno dung, it is now in your filter. With ULSD this is unlikely so i wouldn't freak too much but I would not ignore it either. BD is great for many things and many reasons, mileage isn't one of them...

racertracer · **Posted:** Tue Jun 15, 2010 10:19 pm

Boilermaker2, I agree.

grywlfbg · **Posted:** Sat Jun 19, 2010 2:10 pm

We run B100 always except when traveling and bio is not available. We notice about a 3-4mpg drop w/ B100 from D2. This Jeep has run B100 from 1,800 miles on the odo (~80k now).

I don't have any hard data about the engine life claims (this is our first diesel) but the engine runs noticeably quieter on B100 and B100 does have better lubricity than D2 so it wouldn't surprise me if it did improve longevity.

But as others have said, you run B100 because it's cleaner for the environment and possibly better for your engine, not because it's cheaper.

TJ2 · **Posted:** Sat Jun 19, 2010 3:14 pm

grywlfbg wrote:

But as others have said, you run B100 because it's cleaner for the environment and possibly better for your engine, not because it's cheaper.

Well, that fact that it's cheaper by the gallon doesn't harm the equation.

CRD Joe · **Posted:** Sat Jun 19, 2010 4:15 pm

TJ2 wrote:

grywlfbg wrote:

But as others have said, you run B100 because it's cleaner for the environment and possibly better for your engine, not because it's cheaper.

Well, that fact that it's cheaper by the gallon doesn't harm the equation.

B100 here in the Seattle area is 3.99 a gallon. Standard D2 is 2.99. B100 is only cheaper if you make it yourself!

TJ2 · **Posted:** Sat Jun 19, 2010 4:24 pm

CRD Joe wrote:

TJ2 wrote:

grywlfbg wrote:

But as others have said, you run B100 because it's cleaner for the environment and possibly better for your engine, not because it's cheaper.

Well, that fact that it's cheaper by the gallon doesn't harm the equation.

B100 here in the Seattle area is 3.99 a gallon. Standard D2 is 2.99. B100 is only cheaper if you make it yourself!

I guess it varies with location and demand. B100 is $4/gallon in Moab. In SLC its $2.59/gallon. D2 is $2.82/gallon at the same location.

http://www.americanfreedombiodiesel.com/bio-diesel_links.htm

Note that B20 is more expensive than B100. Supply. . . demand. . . or price fixing in Seattle???

CRD Joe · **Posted:** Sat Jun 19, 2010 5:55 pm

The state of Utah MUST be subsidizing it. Ive never heard of it being less than D2 expect for a very short time two years ago when D2 hit more than 4.00 a gallon. Id use it too if it was cheaper.

stoutdog · **Posted:** Sat Jun 19, 2010 6:17 pm

CRD Joe wrote:

The state of Utah MUST be subsidizing it. Ive never heard of it being less than D2 expect for a very short time two years ago when D2 hit more than 4.00 a gallon. Id use it too if it was cheaper.

It just depends on where you live. It's about $.20 cheaper for bio in AZ right now.

lurch519 · **Posted:** Sun Jun 20, 2010 4:21 am

Girlfriends CRD lost about 2.5 to 3 mpg when we went from b5 to b20 ( more or less, estimated concentration ). No significant drop in mpg in my Dodge at b10.

boilermaker2 · **Posted:** Mon Jun 21, 2010 9:53 am

Didn't want to hijack the thread, posted my response here: The shuttering of biodiesel plants in the US [http://www.lostjeeps.com/forum/phpBB3/viewtopic.php?f=5&t=53681]

fastRob · **Posted:** Mon Jun 21, 2010 10:28 am

Does Bio diesel store well?
If I buy a storage tank, does anyone know what the useful life is?
Or what are the breakdown characteristics?
I hope you guys are paying attention to our fearless leaders.
You might be lucky to be ABLE to buy fuel let alone afford it.

Biodiesel in the mix and MPG drop

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