I need help. Does anyone have any info if Bio diesel will void the warranty. My truck is in the shop right now for chaeck engine light and they said the filter was plugged. They said just for them checking it out they are going to charge me now because I am running Bio Diesel. Has anyone herd this I thought the manuel said we can run like 5 or 10% please help me.

That is so weak if it's true. I sure hope not -- if so that sure takes a large chunk of the bio-diesel market out.

5% per the manual....but if the quality of the fuel is bad...even straight D#2 they can void warranty for related failures.

The manual does give ASTM specs for both the Bio and D#2 prior to blending.

How many miles since you changed the filter?

Do you have a pre-oem filter?

Also...at low blend levels such as 5% or 10% I doubt the bio had anything to do with your filter plugging.

I run up to B100..no problems..but I would not tell that to GM

without any changes really to the motor, the next MY trucks will have 20& biodiesel allowable in the manual...

the dealer's claim is crap IMHO

Biodiesel will clog ure filters when you first switch to it due to the fact that it is mixing with the dino diesel. If you go to any biodiesel site they will have it posted that you need to change your fuel filter when first switching to Biodiesel because it can clog up.

Well I got my truck back and I put some papers in there face from GMs web site about Bio Diesel they said they are very sorry they did not know we could run bio diesel. (Dumb Asses) so they told me to change my fuel filter and bring the truck back. Yes I know the biodiesel will plugg the filters at first. They make the bio diesel at my dads plant so i know all about it.

Biodiesel will clog ure filters when you first switch to it due to the fact that it is mixing with the dino diesel. If you go to any biodiesel site they will have it posted that you need to change your fuel filter when first switching to Biodiesel because it can clog up. Only the sludge in your tank disolved by the alcohol in the biodiesel will clog your filter, that has NOTHING to do with mixing of dino and bio. 100 % bio is far cleaner and better for the engine than dino but might destroy your rubber parts (hoses, fittings...) if they are not made for it - and as said before all the remaining dirt from the dino will be dissolved by the bio and clog the filter (guess thats what happend...).

If the manual says 5 % (which is normal blend anyway in some places) than GM surely can refuse to pay for anything if real bio (100 %) is found in the injection system... :exactly: