What kind of mileage?

[mschn99]

Originally Posted by worzy

I just bought a 99 F250 Super Duty extended cab. So far I have not topped 14.5 mpg, even when I deliberately try to stay off the gas and drive mostly highway. Could there be something wrong with my diesel? It seems to run fine.

milage depends on so many factors......cab style, box lengh, what is in the box or cab that has weight, driving style, lifts, tire size, speed, chips, milage, and on it goes. i dont think 14.5 is extrememly low, although it is towards the bottom of the scale for the 7.3, depending on all the above. i think i would look at all this and consider that before thinking there was something wrong with the motor.

[worzy]

mschn,

I have an extended cab f250 with a short box that has been empty so far. I have stock tires and a stock engine. While on the highway I drove at 70 mph which was probably 3/4 of my miles. I'm new to diesels and Fords, I expected better mileage out of this truck. Maybe it will get better in the summer, I live in wisconsin so I am running winter blend and letting the truck warm up before I drive. I'm planning on doing some performance mods to try to bring my mpg up. Thanks for the response. Any advice is greatly appreciated.

[mschn99]

Originally Posted by worzy

mschn,

I have an extended cab f250 with a short box that has been empty so far. I have stock tires and a stock engine. While on the highway I drove at 70 mph which was probably 3/4 of my miles. I'm new to diesels and Fords, I expected better mileage out of this truck. Maybe it will get better in the summer, I live in wisconsin so I am running winter blend and letting the truck warm up before I drive. I'm planning on doing some performance mods to try to bring my mpg up. Thanks for the response. Any advice is greatly appreciated.

given what you have told me, 14.5 is probably not that bad. at 70, you will get worse milage (the best woud be 55-65). the fact that you let it warm up, which is great, will lower you milage more than you would expect (0.5-5.0 mpg, depending on lengh of warm up), and winter blend fuels are worth 1-2 miles per gallon in themselves depending on a few factors, especially driving style. i would expect approx 18-19 mpg on that truck if it was run on longer driving runs, not shut off, which reduces idle time. ive seen the same truck as high as 22, as low as 16, during summer runs, with minimal idle time and run at normal speeds (not much in town speeds, and nothing over 65-80 mph, depending on gear ratio and driving style). hope this helps and let me or the other guys know if we can help in any other way. i work at a dealer, and we tend to stay away from chips and programmers, but i know superchips, and a lot of others the other guys could help you pick, help with milage if you tune them right, so there is a weath of info on here if you want........hope this helps......Marc

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Last edited by mschn99 : 01-16-2006 at 08:09 PM.

[mschn99]

something i wanted to add, after re reading your post, is a lot of guys expect to buy a diesel and have 25 plus MPG empty, since diesels are capable of such high MPG when towing, and that is not the case. the wonderfull thing about diesels is they do not have a dramatic drop in fuel economy while towing. it is similar to a chevy 454 when comparing to a gas motor. a 454 gets 11mpg.....empty...downhill with a tailwind.....10.9......uphill...towing 20,000 lbs......11.1.....and diesels are kind of the same thing. while your average summer fuel economy may be...lets say 19mpg.....your towing economy on a 20,000 trailer might be 17-18. that is just what the beast was breed for, they are very consistant. and the 7.3, WHEN MAINTAINED PROPERLY, is capable of outliving the rest of the vehicle (trans multiple times, body, frame, and differentials). the ive seen 7.3's that have had pushing a million miles. the truck was falling apart around the motor. ive also seen them that the motor was weak or dusted (improper air cleaner or mainanence) at 75,000. it all depends on the owner.

[worzy]

mschn99,
I've been talking to other diesel owners over the last few days and they all agreed that 14.5 mpg in the winter is not that bad. Thanks for the replies.

[pro99line]

Originally Posted by pro99line

What wire do you check the 5 volts to the map sensor on? I am just curious to check it.

I finally got around to doing this and it seems fine. Left wire had 5.0, middle 1.5, and right did not read anything.

[pro99line]

Originally Posted by Kodiak74

Well I'm not sure how acurate my mpg meter is in my lariet but b4 I tuned the engine with the edge evolution tuner i was getting 15.5 to 16 mpg average. Now I'm doing 25 mpg acorrding to the meter. still waiting to fuel again to get a more acurate avg. I do have a bed cap on mine though. I'll let you know when i refuel what i'm doing

Did you ever get a chance to check your mileage again because this seems almost unthinkable it could change that much. Just curious.

[Mike OB]

Hi Guys, Just got some time to get back on the web . I just returned from a 608 mile trip pulling our 28RK Colorado fifth wheel I got 21.87 miles per gallon. EAT YOUR HEARTS OUT I finaly got it fixed. This is what I have done - 5 inch exhaust all the way, Banks 90 hp chip plus six gun with 62hp , garret tubro housing, dual air intake system custom built, Banks bullit torque converter, banks trans command, plus I wrapped both air tubes from turbo to intake to keep cool, magnet on fuel line. everything here took me from 10 miles per to 14 miles per. Then I pulled all the injectors and resealed them, it took two trips to make it smooth out and jump the mileage up. I forgot Delvac oil. What I discovered is , if you put a fuel pressure gauge on and then crank the engine as you watch the gauge IF THE PRESSURE SPIKS reseal the injectors. I am getting almost 500 hp and 22 miles per in town ,up hill and pulling. some how I guess it was all worth it. I forgot, it started with a broken wire to the map which I ran a second wire, I also have an exhaust brake on it.

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Last edited by Mike OB : 06-25-2006 at 11:48 PM.

[Lone Ranger]

Hello from Australia,

With my Snorkle, and also the front air intake, ramming air into the filter set up, I just did a study on my rig with the same route, same timing, same weather, as I am running about 2 hours 20 minutes a night up to an Arena training QuarterHorses for the NRHA Nationals on in four weeks... Anyways, with a careful study, carrying about a long ton of gear in the bed, I am getting about 19.5 mpg.....

[cblackb]

My last fill up I got just a hair over 22 mpg and that was ALL highway driving at 65 to 70 with the cruise control set and not getting on it even one time. That's basically as good as my truck is going to get until further mods are done. I'm hoping a cold air intake and chip will help it even more but even if it doesn't I'm extremely satisfied with 22 at this point.