Breaking News Bar
posted: 11/4/2012 6:22 AM

Make sure biodiesel won't void warranty

Success - Article sent! close

Q. Im looking at a new vehicle and like the idea of a diesel SUV ... high towing capacity with better fuel efficiency. However, the sales rep at the dealership we visited said something about Illinois diesel-fuel blends have caused many manufacturers to say they will void warranties if it's used, while others have stopped selling diesel engines in the state. What is going on?

A. I have not heard anything about this until now so I called a GM truck dealer I know and a Ford dealer and asked if they were aware of any talk about voiding warranties because of Illinois fuel. In both cases the answer was No.

I needed to educate myself a little on this and this is what I found. It seems that many fuel suppliers are switching from B5 (5 percent biodiesel) to B20 (20 percent biodiesel) fuel and I guess it's been causing some problems. As far as I can tell the new GM and Ford vehicles are OK with B20 but Volkswagen specifically states not to use it.

The service specifications of many vehicles made prior to 2011 say they are compatible with B5 fuel only. Some of the manufacturers don't come out and say that B20 voids the warranty, but they state if any engine problem occurs that can be traced back to substandard fuel, then the warranty may be void.

I have been poking around on the Internet and the information seems to be a little thin as to whether or not there is a problem. Here are a couple of the websites that I found that were helpful: and

If you can locate a service station that sells the B5 then I don't think you will have any problem at all. If you were looking at a new Ford or GM truck then you should be fine using the B20 from what I am reading. You certainly would want to check it in the owner's manual.

You ask what's going on, and I am certain that the Environmental Protection Agency's fingerprints are all over this, just like we may have to deal with worse gas than we already have.

Right now our regular fuel has 10 percent ethanol (E10) and the EPA is talking about moving to 15 percent (E15) in the future. E15 is going to cause lots of problems with many cars unless it is a flex fuel vehicle.

Larry Bell, a contributing energy and environmental writer for, has written an article on the topic called "Ten reasons to care that E15 is on its way to your gas station," which can be found on the Forbes website. He cites a Science magazine report that ethanol produces even more greenhouse gasses than gasoline. Ethanol has also proven to produce less energy and lower gas mileage.

• Douglas Automotive is at 312 S. Hager Ave., Barrington, (847) 381-0454, and 123 Virginia Road, Crystal Lake, (815) 356-0440. For information, visit Send questions to

Article Comments ()
Guidelines: Keep it civil and on topic; no profanity, vulgarity, slurs or personal attacks. People who harass others or joke about tragedies will be blocked. If a comment violates these standards or our terms of service, click the X in the upper right corner of the comment box. To find our more, read our FAQ.