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Why oh why am I only getting 13.0 mpg with 50/50 mix of hwy/city driving? I have a 2005 f-350 quad-cab long box FX4. I have additive for winter and have a light foot when accelerating. What gives??
 

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Winter fuel sucks. Depending on tires and driving conditions 13 is possible. I get 13-15 with my stock 20's and mixed use. My 02 7.3 gets 15-17 with 35's...
 

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Diesel #1 (the winter blend) will get less mileage the diesel #2 due to it's lower energy content.
 

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I have a 2005 F350 PSD, super cab 4x4. I checked it over Christmas on a trip and got around 18mpg on the highway and with a mix of city/highway driving I got around 15-16. I'm not really that light on the pedal, but I'm no lead foot either.

I towed a F150 on a trailer for about 3 hours and ended up getting about 13mpg average. Most of that towing was 50/50 between 55mph back roads and 70mph highway
 

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I just did a run to Ga and back and got 20.3 mpg average at 65mph on b100.
truck in sig. I got one of the good ones.
 

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low mpg's as well

Just picked up an 06 F350 CC Lariat and the tip 'puter is telling me that I'm averaging only 8.8 around town which for now is 100% of my travel. Running winter blend with cetane / anti-gel boost additive. I'd love to be getting even the 13 - 15 average that most are getting.
 

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im getting around 6-8 mpg got a 9' plow on it with a new man. engine in it , but i dont feel bad we have 10 brand new gas fords at work (2009 f-250 ext. cabs) all them get 6 to 9 mpg I love the guys who say they get 20 + mpg i will say my uncle got close but hes completey stock and it takes him 2 miles to get up to 45 mph he can honestly tell someone 18mpg , im sure thats where the twentys come from
 

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Getting 13 with a mix of city and highway here too. Also light on the foot, geez what am I doing wrong?
How's your maintenance schedule? How are the brakes? When's the last time you had the trans serviced? How about tires? Whats the wear pattern look like? Pressure? Font hubs in? Air filter ok? How about mods? Lifted? Big tires? How much do you idle? Do you turn it off when fueling? Keep the climate controls running for over three minutes when stopped?

All this stuff adds up.

I've noticed that with ULSD, I've dropped 1 m/g. Used to be a solid 18+, now its 17+. I've tracked every drop of fuel through the truck in a spreadsheet. Average lifetime fuel usage for 76+k miles, 16.9, including towing. Lowest ever 11.6, towing 7k#s at 70m/h. Highest ever 19.8. Longest tank (38g) 745. About 80% of my drivng is I-5 60 mile RT.

Milage / Economy is a head game / lifestyle, and you have to be willing to play.

OMC
 

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Discussion Starter · #12 · (Edited)
How's your maintenance schedule? How are the brakes? When's the last time you had the trans serviced? How about tires? Whats the wear pattern look like? Pressure? Font hubs in? Air filter ok? How about mods? Lifted? Big tires? How much do you idle? Do you turn it off when fueling? Keep the climate controls running for over three minutes when stopped?

All this stuff adds up.

I've noticed that with ULSD, I've dropped 1 m/g. Used to be a solid 18+, now its 17+. I've tracked every drop of fuel through the truck in a spreadsheet. Average lifetime fuel usage for 76+k miles, 16.9, including towing. Lowest ever 11.6, towing 7k#s at 70m/h. Highest ever 19.8. Longest tank (38g) 745. About 80% of my drivng is I-5 60 mile RT.

Milage / Economy is a head game / lifestyle, and you have to be willing to play.

OMC
OMC, thanks for the response, I will do my best to answer all questions fully. Let me know what I can/should be doing to increase my mpg.

My maintenance schedule is as follows.
Bought the truck used at 104,000 miles, is now at 111,729
-Changed oil at 107,000 miles
-Changed fuel filters at 107,000 miles
-Brakes have plenty of wear left
-Changed tires to 325/65/R18's Nitto Terra Grapplers, filled to 60PSI
-Front Hubs are set to auto lock
-I only idle at stop lights
-I turn truck off when fueling
-I have climate controls on when driving, but do not idle much so not at all there. Minimal A/C use
-Never had had trans flush done.
-Just changed air box, stock

Again please let me know all thoughts on this, thanks.
 

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OMC, thanks for the response, I will do my best to answer all questions fully. Let me know what I can/should be doing to increase my mpg.

My maintenance schedule is as follows.
Bought the truck used at 104,000 miles, is now at 111,729
-Changed oil at 107,000 miles
-Changed fuel filters at 107,000 miles
-Brakes have plenty of wear left
-Changed tires to 325/65/R18's Nitto Terra Grapplers, filled to 60PSI
-Front Hubs are set to auto lock
-I only idle at stop lights
-I turn truck off when fueling
-I have climate controls on when driving, but do not idle much so not at all there. Minimal A/C use
-Never had had trans flush done.
-Just changed air box, stock

Again please let me know all thoughts on this, thanks.
Does the truck have a lift with those tires? The tires are too big for "best" economy. I wouldn't go much larger than the 265's I have on mine for decent economy. They don't hurt so bad if you're doing a lot of traffic at low speed, but anything over 45, & they are definitly NOT HELPING. They look good, but the don't help economy. Have you taken into account the larger tire size when calculating your economy? I don't remember the adjustment factor, but with larger tires, your odometer is not reading correctly, and you need to adjust for that when calc'ing your m/g.

Any air you let under the truck creates drag. That along with speed (frontal area pressure) will kill economy. The faster you go, the more power it takes to overcome the drag & pressure, and its not a linear function, its a cube function. It gets worse much more rapidly the faster you try & go.

About the brakes - are they dragging? That'll sap economy (and remember to check your trailer brakes too). Tailgate should always be kept in the upright position too. Tailgate down creates a drag vortex behind the truck.

Otherwise, keep up your maintenance & enjoy your truck!

OMC
 

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I get 14.5 to 16. On a rare occasion I can get 17 on a highway trip with the cruise set @ 70. When I tow my 36ft TT I get 7 to 9 mpg. I change my filters & I run Power Service additive. I recently had my EGR Cooler & Oil Cooler replaced & my mileage came up from the 13's I was getting prior to the changeout. I don't mind the empty mileage but I thought my towing mileage would be better. Truck is bone stock.
 

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The 2008 year I traveled 20,116 miles
Fuel used 1.434.22 Gallons
MPG = 14.03 and that includes 15% of the miles were towing a TT.
 

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I'm getting about 14 mixed city & highway & 10 pulling a trailer with 285/75/16 tires and engine running like crap. When it's running good I get 16 mixed driving and 13 towing. Wish I could get it running good again. :icon_rolleyes:
 

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Lately (on winter fuel) I've gotten about 13 ~ 14 mpg, mostly pulling an open utility trailer with a couple of ATVs, 80% 60mph highways, 20% in town.

In the summer with nothing in tow under the same circumstances I get around 17 ~18 mpg.
 

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Im averaging 12 without flashpaq, 13.5 with it and thats all city driving.
 

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14.7 average, mostly city. 21 at 55, 18.5 at 75, when stock. Haven't had enough time on the tuner to tell for sure but looks like 17 average, mostly city.
 
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