Duramax And ULSD

[Montana Sky]

indy,

I ran into ULSD this summer during my 7 week trip to Goshen and back. Over 7,000 miles I had a pretty good account for mileage between LSD and ULSD. Used the same route for more than 3/4 of the trip, so I know the terrain was not a factor. I am one of those guys who also runs a fuel log, have done so since the day I bought this truck. (actually since the day I bought any of my vehicles) The loss of fuel economy is right there in black and white. I travel the same 65 miles into town and back at the same speed every day from April - October, I am pretty sure over a 6 month period on the same road I can say my average has dropped since running USLD.

Another example, I run from Spokane over to Seattle at least once if not twice a month. In November I ran ULSD on both trips, the only difference was 1 trip was made running no additives, the 2nd had GM Diesel Fuel Conditioner in the tank. At 75mph the first trip averaged 19.2 mpg, the 2nd trip averaged 22.4 mpg. Destination was the same place and route was the same.

I give these two examples to show you where my thoughts and opinions are coming from on this new fuel. I am not an expert, nor am I trying to start a fight. I am just looking at the actual results my truck has provided and sharing my experience.

[indy roadrunner]

Montana Sky, you are doing better than I am doing at that MPG. I can't get over 18 MPG driving over 65. At 70 I am probably in the 17's. Most of my driving is interstate, I do very little "in town".
Course I am just now getting close to the 10,000 mile marker so still in the break-in period.

[Montana Sky]

indy,

You have a long way to go until you get that motor broke in. Get some more miles on that baby, it will improve.

[aljolleyjr]

Montana Sky & Indy:
You are both blowing me out the water. I get 15mpg solo and after an 8400 miles trip to the west coast I averaged right at 9mpg. I have an 06 LBZ with 11000 miles on it.