Some gas stations have ultra low sulfer diesel and some have low sulfer diesel. I always try to find the low sulfer diesel cause it makes the truck smoke a bit more and it may just be in my head but I seem to get better gas mileage with the low sulfer stuff. So what does it do to the truck when you run either? I understand one has lower sulfer. Where do they sell regular diesel? Drag strip or something??

 

The trend is towards the Ultra low. The new 07 must run ULSD Your 05 will run on either. It all depends on your location as to what you can get. I run a semi and I too have noticed a slight drop in fuel milage. This could also be from winter blended fuel. The ULSD won't lubricate as well so I'm told. When I have to use ULSD I put an additive like Lucas fuel treatment in. It helps to lubricate and clean the injectors.

 

I live near Austin and currently some stations still sell LSD, but have ULSD.
I use the LSD and my 04 still has the wonderful diesel smell. Go to the Flying J web page and under diesel fuel prices they show their stations that sell both.

Pete