I just got back from a "full tank" run w/ avg speed at 65 which is roughly 1700rpm.. i was right at 14 which is atleast 2mpg less than what i had around Sept "10".. Could i still running through winter blended fuel??

Honestly I'd hate to get your hopes up. I would just tell you at this point go ahead and mod, but mod for power, don't expect to get any better. I get 14-15 in my extended cab short bed 4x4 auto. Never mod for mileage, but be happy if you get some.

Very possible... what did the fuel look like last time you filled up?

same as it always does. Why, should i see a difference?

Because summer fuel and winter blend are different colors.

Honestly, i don't see the difference. when you say "different color", how much difference in color? Certainly not like "off road" (red)color..

Is it just a shade difference?

After doing some more research you may or may not see a color change dependant on what they mix it with. Normally winter blend is #1 and #2 mixed together, and the ratio varies depending on how far north you go. Some places don't add #1, but they will add conditioners. In upstate NY here I can see the difference, reg summer #2 looks like plain old diesel, yellowish kind of. The winter blend looks blue/greenish here.

yeah city driving it gets realyl piss ass poor MPG. Ill take it to the dealer and see if they can figure it out. Since its still under warranty. My brother has a Crewed 07 shortbed and keeps telling me he gets about 16 to 18 average. My truck is a crewed longbed 350. Stock tires as well. So relly need to get to the bottom of why Im not getting better mpg.

I have buddies with 05 and 06 CC/SB's with 6" lifts and 37" tires on stock 3.73 gearing, running extreme tunes getting 13mpg driving like idiots.

Apparently i'm not far enough north in MI to see the difference. It's probably something the dealer did without me knowing:bat:

Thanks for the info!!

yeah def sounds like I got something going on. Sucks when I can drain the tank sometimes in 300 miles. Only time I really get on it is trying to get on the dang freeway here. Highway Im usually at 70. Or at least keeping the tach under 2k. Cause once its over 2k. the mpg drops drasticly. Just trying to think of what it could be?

I did the Oasis report from the link here. And found that within the first month of this truck being bought the engine was replaced along with the injector loom? Very strange. And then I think at about 30k miles the Oil/Egr coolers were replaced. I havnt really had any major problems wiht the truck other then back when the Odo and Speedometer were acting funny by shutting off or flipping 4 miles per every one I drove. Got that fixed. Found some connections under the fuse box were loose.. have cleaned the EGR and put in new O rings. But that was about 7k miles ago. Maybe I should check that again? Had the Turbo serviced because the vanes were stuck. Ford cleaned that and replaced a ring in that. cant remember what one it was though.
Then the Fuel pressure regulator started leaking. Ford fixed that also. Jusrt since then the MPG has been even worse. (Question) with the regulator leaking. Whould that cause the Fuel prssure to drop and mess up the injectors? or anything else I should worry about?

Wife has the truck today so Ill try to get into Ford this week or next. Need to find someone with a Scanner so i can check codes if its throwing any.