Why 2007+ Vehicles Don’t Like Biodiesel

Posted: January 21, 2011 in GREEN, Secrets, Table Of Contents, TRUTH / Occupy

taken from:



Why 2007+ Vehicles Don’t Like Biodiesel

I just had a great chat with Jeff @ SunBreak Biofuels (Great guy!) & learned some interesting things about why these new fangled 2007+ Emission Diesel Vehicles aren’t liking Biodiesel.

Here’s what he shared….
To meet the new emission standards, diesel engine manufacturers have added a “post-combustion” burst of fuel into the cylinder.

What’s this mean?
Well, it means that after the compression stroke is done and the cylinder is in the down position, as it heads into the exhaust stroke, the fuel injector sprays a dose of fuel into the cylinder.

The theory is that by spraying fuel into an already heated cylinder chamber, the heat will vaporize the fuel (not burn it, just vaporize it) and the exhaust stroke will push this unburned fuel out with the exhaust.

This unburned fuel then hits the new Diesel Particulate Filters (DPF) and helps to burn off the particulates built up on the DPF.

In otherwords, the engine manufacturers have found that by squirting unburned fuel into the exhaust, it hits the DPF with hot exhaust gasses & more fully burns off the particulates that have built up on the DPF’s.

The Problem With Biodiesel
Biodiesel is “leaking” into the crankcase oil.

This happens because Biodiesel doesn’t “vaporize” as fast as diesel fuel (because it has a much higher boiling point, one of it’s supposed “strong points”).

Because it doesn’t vaporize as well, a portion of it sticks to the piston walls instead of all going out with the exhaust gasses.

As the piston goes back down and then heads back up into the compression stroke, the Biodiesel is blowing right past the rings down into the crankcase and getting into the engine oil.

But wait, it gets worse!

Biodiesel in engine oil isn’t ALL that bad because, well, it does have a bit of viscosity to it (quite a bit in fact, enough that we like to even brag about it)….but the problem is that over time the Biodiesel raises the level of the oil in the crank-case to the point that the crankshaft can start “splashing” in the Biodiesel-laden engine oil.

This can cause “foaming” to occur, and then as the foam builds up inside the engine, “too much of a good thing” can start to hurt the components.

So how bad is it?
Well, according to VW, after using B5 in a new engine for a few thousand miles, they drained out the crankcase oil and over 40% of the oil was contaminated with Biodiesel.

According to Jeff Brandt, even in his new Dodge Ram, he’s seen contamination building up with as little as 1800 miles of driving.

He said when he drained out the oil it was really liquidy, almost like the consistency of water.

What About The DPF?
My initial thought with these things was that the Biodiesel was also fouling these, but Jeff’s take is that the exhaust gasses are hot enough that any Bio that gets in there is doing it’s job & burning right & he’s yet to hear of a plugged DPF because of Biodiesel use in the vehicle.

So What Can Be Done?
Some engine manufacturer’s have installed a small fuel injector in the exhaust itself to spray the fuel with instead of adding a “post-injection” squirt of fuel in the cylinder.

This gets rid of the issue completely.

For those engines that squirt the fuel as a “Post-combustion injection” (after the combustion has occured in the piston), it may be possible to override the computer and stop the “post-combustion” fuel being injected; but it’s tricky.

If you don’t remove the DPF and you do eliminate this “post injection” it can cause the DPF’s to get plugged up.

You can also remove the DPF on the vehicle, but this technically makes the vehicle illegal to drive on public roads making it an “off-road vehicle” only.

The other option would be to override the computer so that it will only perform the post-combustion injection if you’re running Diesel fuel, but that’d require some sort of manual intervention from the driver to tell the computer that there’s only diesel in the tank.

Jeff thinks that we may see a couple things happen in the near future.
1) Someone may be able to develop an additive that can lower Biodiesel’s boiling point (kind of far fetched admittedly and a lot of work to do)
2) Aftermarket “tuning chips” will be made available to kill that “post-combustion” injection in the computer
3) People will just rip out the DPF’s and kill the “post-combustion injection” altogether & drive the trucks on road anyway.

By the way, killing that Post-combustion injection event may even get you a couple extra miles per gallon.

Either way, it’s not a great thing for those of us wanting to run high blends of Biodiesel in new diesel vehicles.

Neither he nor I know exactly how Ford & GM are accomplishing reducing the emissions, but Jeff thinks that they’re both doing something similar (post-combusion injection event).

…for those of you wanting to run Bio in your new post emission vehicle, be sure to check the engine oil constantly to ensure the level isn’t getting too high and also change the oil out more often if you plan to run high blends.

Anyway, figured since this was news to me I thought I’d pass it on.

Jeff said if he has time he’ll come in here & post to this thread with anything additional he hears about as well.

Additional Resources
I’ll be adding to this section as people post resources & forum posts about this issue.

Biodiesel Magazine Article
Understanding the Post-injection Problem

Diesel Power Magazine
Article on how to remove a DPF filter (This article has “Mysteriously” been removed…hmmmm)
(WARNING: Removing the DPF makes your truck “For Off-Road Use Only” and voids the warranty.)

Infopop Forum Posts
B100 use in post-injection modern diesels, leading to high engine wear
Biodiesel getting into engine oil
Mechanics Please Help: Problems with ’07 6.7L Dodge

BurnVeg Forum Post:
Warning:danger of using VO/>B5 on many vehicles >=2007

Diesel Place Forum Post:
Removing a DPF on a Duramax

Below is a list of engine manufacturers that produce diesel engines sold in the United States.

If you’d like to see this issue changed in the future, be sure to write to your favorite engine manufacturer below and let them know that you’d like to see their DPF design changed so as to allow Biodiesel to be used in blends higher than B5 in their engines.

Case New Holland
Harold Boyanovsky
President and Chief Executive Officer
CHN Global N.V.
100 South Saunders Road
Lake Forest, IL 60045 USA

Theodore M Solso
Chairman and Chief Executive Officer
PO Box 3005
Columbus IN 47202-3005

G. Richard Wagoner, Jr
Chairman and Chief Executive Officer
General Motors
300 Renaissance Center
Detroit, MI 48265

Len Hunt
Executive Vice President
Volkswagen of America, Inc.
2200 Ferdinand Porsche Road
Herndon, VA 20171

James Owens
Chairman and Chief Executive Officer
Caterpillar Inc.
100 NE Adams Street,
Peoria, Illinois 61629

Detroit Diesel
Carsten Reinhardt
President and Chief Executive Officer
Detroit Diesel Corporation
13400 Outer Dr. West
Detroit, MI 48239-4001

Daniel Ustian
President and Chief Executive Officer
Navistar International
4201 Winfield Rd
Warrenville, IL 60555

Ernst Lieb
President and CEO
Mercedes-Benz USA
Mercedes Benz One Mercedes Drive
P.O. Box 350
Montvale, New Jersey 07645

Robert Nardelli
Chairman and Chief Executive Officer
Chrysler LLC.
PO Box 21-8004
Auburn Hills, MI 48321-8004

Ford Motor Company
Alan Mulally
President and CEO
Ford Motor Company
The American Rd.
Dearborn, MI 28121

John Deere
Robert W. Lane
Chairman and Chief Executive Officer
Deere & Company World Headquarters
One John Deere Place
Moline, Illinois 61265

John Mendel
Executive Vice President
American Honda Motor Co.
1919 Torrance Blvd.
Torrance, CA 90501

For a great example of points to cover in your letter, be sure to check out the Spring 2009 Biodiesel Magazine article by Kumar Plocher (page 6). See more info on Biodiesel Smarter here:

Feel free to comment, correct, or post to this….this was just news to me & I thought I’d pass it on.



This message has been edited. Last edited by: Graydon Blair, August 12, 2009 01:10 PM August 12, 2009 12:10 PM

Utah Biodiesel Supply – Biodiesel Supplies, Parts, Kits, Tutorials, Decals & More
Free Biodiesel Tutorial Videos – Learn to make Biodiesel through videos!
Utah Biodiesel Facebook Page – Stay up to date on all things Biodiesel!
Biodiesel Review – A free newsletter with tips & tricks on making Biodiesel
Biodiesel Pictures – A free place to post your biodiesel equipment pictures

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s