After looking around here and elsewhere, I still haven't been able to determine when or if our trucks were first designed to run on the ULSD.

But....maybe I just missed that little piece of info. ;)

I believe our 04.5's were built and designed for LSD and before the mandate for ULSD. The 07's and newer are the only ones "designed" for it.

2006+ engines as far as I know of where designed for ULSD...

Thanks guys! :thumbsup

Moparman, this may be a dumb question so forgive me but I am new to the Diesel world. If my '07 was designed for the new ULSD fuel is there any gain or reason to mix 2 stroke oil in the fuel? Also, some guys (not online) have told me because my truck was built in late '06, and it doesn't say use ULSD anywhere on it, that I don't have a ULSD engine. Does any of this make sense? Sorry If I hijacked this thread but it seemed relevent to the discussion. - Eveready77

Before I bought my 07 last July I asked the dealer mechanics if I should buy a 5.9L or the 6.7L. ULSD was a concern of mine and the availability of it. The answer was the 5.9 because it can burn both. As far as using a additive Mike has a lot of good research on this site to read. If you are able to get bio-diesel where you are at then you really don't need a additive as there is great lubrication and cleaning properties in bio-diesel. Even more then 2-stroke oil. I am in Minnesota and 2% bio-diesel is mandated. For that reason I don't use any additive.

I believe we have bio available at a station or maybe two here in Chattanooga. The price is generally the same as dino Diesel so I haven't tried it out yet. That and I have been told that when you start using bio you need to change your fuel filter more often at first because of the better cleaning you mentioned. I would like to explore making my own bio but for now obtaining oil, and time to do it seems to be the hold up. As for additives, I did start using Diesel Kleen on this last tank on the reccomendation of a couple friends.

Moparman, this may be a dumb question so forgive me but I am new to the Diesel world. If my '07 was designed for the new ULSD fuel is there any gain or reason to mix 2 stroke oil in the fuel? Also, some guys (not online) have told me because my truck was built in late '06, and it doesn't say use ULSD anywhere on it, that I don't have a ULSD engine. Does any of this make sense? Sorry If I hijacked this thread but it seemed relevent to the discussion. - Eveready77

I would be very careful about mixing 2 cycle oil with newer 5.9L and 6.7L engines. I know the 6.7L are having problems with just ULSD and the DPF but as for the 5.9L I got very little information. I would say there is no real need for adding 2 cycle oil to ULSD fuel. Being that all the fuel system is designed for ULSD.

I believe we have bio available at a station or maybe two here in Chattanooga. The price is generally the same as dino Diesel so I haven't tried it out yet. That and I have been told that when you start using bio you need to change your fuel filter more often at first because of the better cleaning you mentioned. I would like to explore making my own bio but for now obtaining oil, and time to do it seems to be the hold up. As for additives, I did start using Diesel Kleen on this last tank on the reccomendation of a couple friends.

The idea of cleaning is a myth... My truck has never in its life seen BIO fuels ever... Take a look at my fuel tank after 6 years and 127K miles...

The little black bits are the drill crumbs from the draw straw install...

What is happening is the BIO fuel is eating at different materials in the fuel system like rubber o-ring (older vehicles) and such... There have been finding that some sources don't wash or filter there fuel properly either... That is why everyone is complaining about having to change the fuel filters so often. The methanol and lye tends to be great solvents but they also attack some materials...

I've got another thread here on BIO-fuels as well...

viewtopic.php?f=14&t=267

viewtopic.php?f=14&t=117

So be careful and know your source concerning BIO-fuels...