Its not just the fuel that causes fuel mileage reduction in cold weather. Operators let trucks warm up longer, alternators draw more power to compensate for longer glowplug/heating grid on times and heater and defroster operation. ECM strategys for cold engine starting and warmup can be differant. DEF tanks got to get warmed up. Lubricants are thicker and cause more drag. Increased wheel spin on slick roads. etc. etc.

 

Well said. It's not just the winter fuel.

 

I just posted this on another thread, but the additional drag from cold air also affects mileage.

 

The new valance is on and mileage is still 17-20. Much better, but like I said, I can't wait until spring gets here.

 

me either...I hate the cold more than the winter blend fuel

 

I have been getting crappy combined mileage for a few months (maybe 15.5-16.5) unloaded in my CC 3.55 4x4 truck. Most of those miles are short enough that the engine does not come up to full temp. I have 2 temp values on my screen and 2 "real" gauges. I think one of the "real" gauges is coolant temp, and that is the slowest to center.

Anyways, twice in the last month I have made a 200 mile trip through moderately hilly terrain, at 1500RPM in 6th, mostly, (64MPH?) and gotten, hand calculated, 20MPG (19.8 to be exact.)

(I do use Diesel Kleen.)

So from what I can tell, for me, there are 2 big factors that affect my unloaded mileage:

1 - full operating temp
2 - go slow

YMMV

 

Full operating temp is something that has been noticed by several folks here. I think it's fair to say that the engine uses a LOT of fuel when it's cold as evidenced by the MPG gauge and history screen.

Thanks for the factual input....

 

Hi newbie here.

I've gotten a lot of good information from this site, but I'm at a loss.

This morning was unlike any other - 52'ish degrees. I noticed that my truck "felt different". I noticed that I lost about 6-8 mpg (accoring to the computer). I know the roads, I travel them every day. "Normal" is around 18-18.5. This morning was no better than 11.2-12.4. I'm working on the same gas that has been in the tank for the past week (now just below 1/2). I understand if it were new gas/bad gas.

Absolutely nothing different this morning than last night when I drove it. Someone suggested replacing the fuel filter. I've got about 9500 miles and the oil was changed at about 7000 miles (like Ford told me).

I don't think anyone mess with my fuel. Could be, but I'm pretty certain not.

Any other suggestions?

Thanks.

*It is a 2011 F350, 6.7, CC, 4x4, Lariat. Bone stock, nothing "modified".

 

Cold air is more dense........ also, makes for a stronger combustion.
I tow the same trailer (2008 model). I had been using a 2008 Dodge 3500. A month and a half ago I sold the Dodge and bought a 2011 F-350 FX4 Ultimate Lariat CC LB ELD 3.55 / 11.5GVWR. Love the truck so far. Just finished installing a B&W under bed gooseneck/5th wheel hitch. Haven't towed yet. This weekend I hope. Any info on fuel mileage towing the 5th wheel?

 

It could be possible you stopped an active regen that started prior to shutdown the evening before then once the engine was warmed up a little, the active regen process began again because the soot GPL was at or above 2.66.
How far do you drive?

Also, best to leave the habit of using the word "gas" in your past.
Might keep you out of trouble in the future.

 

Man, my truck has only 3700 miles.... i barely get 19 mpg highway, I live in Florida and don't think they winterize the fuel. I would like to see that kinda mileage!

 

I really don't think you can judge your mileage by watching the instant reading on the command center for a minute or two. As mentioned you might just have been in Active Regen at the moment when you looked at the command center instant mileage.

Calculate your mileage averaged over the entire tank of fuel and if it has dropped off, then you might be concerned. But being worried about your mileage based on 5 minutes of road time is waste of effort. Heck one good flooring of the pedal pulling away from a traffic light will mess up a 5 minute avg.

Refineries started shipping winter blend fuel Oct 1st. So anything you buy now will probably be winter blend which has less BTU's than the Summer blend and gives lower mileage. So everybody can expect to see a drop in their fuel mileage this month.

You say your truck "Felt Different" as in how did it feel different? Rough idle, having to push the accelerator farther for same results, missing or coughing? Bad fuel, filters plugged and starving fuel system, or just cooler weather and truck not warmed up to normal temps?

I'm not sure that your filters are the problem, no mention was made of how many miles you have on your current filter, but I assume they are factory filters with 9500 miles on them since you bought the truck. Filters are cheap enough that I'm changing my Fuel and Air filters every 15,000 miles. It takes all of 15-20 minutes to change both fuel filters and the air filter. I'd rather change mine on a nice fall day at 70° on a dry driveway, than in January at 10° with slush on the ground.

 

Have a 40ft 18k lb Raptor. Usually get high 8s. Towed a 17 k lb gooseneck and got 11. I have 35s also.

 

Your are correct about using the word “gas” with my truck. Hard habit to break. I didn’t notice the regen process starting, but you are correct that it might have started.

 

Thank you. I did leave out a little info as I didn’t want to type a short novel (I guess I should have included more info, though, if I was hoping for “help” with my issue). I drive about 16 miles every morning/evening. Mostly rural roads. 4 stops signs on a 40 MPH road over 3 miles, 1 traffic light on a 55 MPH road that is usually green for the direction that I drive. Then it is to freeway speed (70 MPH in one section, dropping to 60 MPH in another section – for a total of about 10 miles). Off the freeway in a 35 MPH zone, dropping to 15 MPH to enter where I work.

<O</O
Yes “feeling different” by having to push the gas pedal just a little bit more to get the same results that I’ve come accustomed to. Idling appeared fine, engine didn’t sound any different. Nothing noticeable other than the gas pedal.

The fuel filters were also brought up by a couple other people that I talked with. Yes, they are the stock filters. It was suggested change them every-other oil change, which I’m probably going to do.