Hey guys!
I actually, under the same name (biofuelsdude), have responded to the boys and girls on the www.duramaxforum.com site concerning this. Go under alternative fuels and you will see a load of info regarding the duramax motor and alternative fuels. Anyways. Bad news ladies and/or gentleman. The DPF on your trucks was designed to get rid of nitrogen oxide emissions (Chemical sign: NO2) which currently makes the United States the leader in strict diesel emissions. I know, the United States leading in emission standards?! What?! Well if you may or may not know biodiesel reduces most all forms of emissions when burned in a diesel regardless of how old they are. The only thing biodiesel and veggie oil increase in the way of emissions is guess what? Nitrogen oxide emissions. How do you get rid of this emission? For awhile it has been hard but the usual way to do it is by retard timing, which cuts into your mileage and increases soot output.
Are there other ways to get around this? Well automakers are getting clever but they have not reached a nitrogen oxide emission system in which biofuels are safe to use. Its a catch 22 really. You can get a very clean diesel that is cleaner then a gasoline engine but can not burn biodiesel or you could get a older diesel that may have a lot of miles on the clock but can run veggie oil or biodiesel. The answer for you both, anything above 5% biodiesel used (B5) will void the warrenty. Personally, if I owned one run B20. How on earth, besides telling them, would they ever know that you had put more then 5% of biodiesel in you fuel tank ever?!? I say before going to the dealer for whatever reason, just to be safe, run B5 or less so if they snoop around and check your fuel system you will be in the clear. I do not know exactly how this will effect the expensive emission equipment; however, I do know that if you wish be safe rather then sorry I could understand that. After all, these trucks are not bought with change from the piggy bank. I'm sure you guys or gals are working stiffs like me and every dollar counts.
One guy on the duramax forum has ripped off his catback exhaust because he cared about mileage and cost of fuel over warrenty work. Frankly the warrenty is as good as the guy that sold it to you. So for what its worth and what you are willing to risk, it may be an option for the new trucks to get rid of the emission equipment. Lurk around and see what those guys have to offer. Many duramax trucks from the 2001-2006 range are running biodiesel,waste veggie oil, etc. However, with these newer trucks it has become somewhat impossible without lots of red tape to cover up.
For now it seems biodiesel will be on the back burner for new diesel.
Erik
