Is 11.9 mpg correct for a 99 250?????????

[mick883]

I am new to the diesel scene. I bought a 99 F250 crew cab in the summer. I went with diesel since everyone tells me how much better the gas milage is than a gasser. Well is 11.9 really all that I should expect? Have only one friend to compare to and he has a 97 F350 stock with the same tires on it and he gets 17 mpg!!! That is more what I expect.

Are there things I should be looking into that could be making my truck get less MPG??

I have no exhaust, no chip, no intake. the only thing it has is a pair of BFG A/T 315/75/r16 tires. I know they will reduce my milage a bit, but not that much.

[Tex99F-250]

i Have a early 99 and it gets 15 around town. it is a stock 2wd. make sure the tires are properly inflated, that will kill the milage.

[a1l71700]

I have an early 99 that is stock right now. I get 14.5 mpg average.

[rednekexprez]

open up the exhaust..If ya dont want to spend much money go to a muffler shop and have them staight pipe it...Also a after market airfilter setup this will help a chip wouldnt hurt either ....

[bucwheat]

I have a 97 F-350 DRW crew cab, about 8700lbs and get 16 -17 mpg .

[strokin_early_99]

Originally Posted by mick883

I am new to the diesel scene. I bought a 99 F250 crew cab in the summer. I went with diesel since everyone tells me how much better the gas milage is than a gasser. Well is 11.9 really all that I should expect? Have only one friend to compare to and he has a 97 F350 stock with the same tires on it and he gets 17 mpg!!! That is more what I expect.

Are there things I should be looking into that could be making my truck get less MPG??

I have no exhaust, no chip, no intake. the only thing it has is a pair of BFG A/T 315/75/r16 tires. I know they will reduce my milage a bit, but not that much.

35" tires and no mods to make it more efficient will kill your mileage. I would bet your buddie has 4.10 gears and that makes a difference as well. I would start looking at the up pipes for leaks and the intercooler tubes to see if they are tight.

When was the last fuel filter and air filter change? Tire inflated to 50psi?

[mick883]

strokin early 99,

Thanks for the advice. I haven't changed the air or fuel filter since I bought it this summer. How often do you change them? I only have done the oil and filter so far. Tires are up to 50 psi.

[cogs69]

Don't forget that since you are running larger tires, your odometer is reading less miles than you are actually traveling. If you don't get a tuner to correct your odometer, you need to figure in the percentage into your calculations.

[powerstrokes only]

I would change the air and fuel filter FIRST THING! The early '99 got it's air from the wheel well, I went through one a month with the truck I had. Those two filters can kill milage! You can upgrade the air box to what the '99.5 had, gets its air from the grill. I did not really like my early '99, only kept it a year and bought a '99.5, what a huge difference!!!!!!! It had a bigger turbo and about twice as much pulling power. My rule of thumb on the air filter is if the gauge moves any at all change it no matter how few the miles are on the filter. One bad tank of fuel can ruin a fuel filter too, then you have no power and terrible milage. My '99's both averaged 16-16.5 empty, and I always set my cruise on 82mph.. Good luck!

[willholl79]

my 96 dually with 4.10 gears gets 18mpg

my 01(6spd) with 3.73s and 315s gets 18mpg