Is 14MPG bad or is it not in a 03 Dodge 2500 Crew Cab short box? I have tried driving it civil and not so civil and all I can get is 14MPG. I have been told I should be getting 18 to 19 and that I should join DTR to find out. So I joined and here I am. I have a Edge EZ set at the highest setting, 35 inch tires and a Aero Turbin muffler. I have tried gas additives and to no avail I can't get any better then 14MPG mileage out of this truck. I don't haul much af anything eiter. Any recommendations or am I asking to much from this truck? Once I was able to get 18 and the only thing I can think of that was different was the fuel. Can there be that much difference in fuel. I diod get that tank of fuel in Wyoming and I live in Colorado.

Thanks in advance for any ideas or things to try. I also tried searching this website and maybe I just aint using the right words to search for. If there are any posts on this subject please help me find it.

 

winter fuel will give you less mpg because it is a mixture of #1 and# 2 diesel
during the summer you will ge using #2

 

I'd say you're not doing too badly if that's your mileage using gas....

 

Did you set the speedometer for your big tires?

 

LOL!!! I guess I missed that one "GAS" thing. I caught the other ones where I used the word "FUEL".

I haven't set my speedo for the bigger tires and not sure how to do that, however, does there need to be any changes in the computer to account for anything I have changed, larger tires, etc.

 

Dealer can set speedo and yes your mpg will read low since your speedo is reading slow.

 

Larger tires will effect your speedometer and odometer reading. If you are hand calculating your mileage you will see some effect in that your odometer will be under-estimating the mileage driven by a factor equal to the ratio of your stock tire to your current tire diameter... i.e., if the truck came with 30" tires and you're now using 33" tires, you should multiply your odometer reading by the ratio 33/30 or 1.1 to get your actual odometer reading... same goes for your speedometer.

 

Never heard of using difference in tire DIAMETERS for a multiplier. More accurate to use a fraction based on circumference, or revolutions per mile.... no?

RJ

 

I do understand the speedo would be off and the mileage is actually better then what I am calculating however, If I calculate my MPG by the speedo I would get the same answer to the calculation no matter what size tire I put on, within reason of course.is 14 MPG standard or average for an 03 deisel.

 

You are going to go a lot farther on 35's per tank than the stock 32's or so. My truck was off by 5 mph or so when I put the 315's on. Your truck thinks its going so far per turn but you are covering more ground.

You should be doing better than 14 highway driving. The 03-04's get the best mileage of the 3rd gens, and I remember there being a flash for the newer trucks to improve mileage, but not for the 555's.

 

I agree, 14 is very poor fuel economy. Even is you are off a couple of mpg's in your calculations due to tire size not matched to the speedometer, it is still poor fuel economy.

 

circumference of a circle is pi x diameter so the pi would cancel out and you are left with d2/d1... since the circumference is the distance a wheel would travel in a revolution, revs per mile is just a longer calculation and you would end up canceling out the 5280 ft/mile and pi and still end up at d2/d1....

 

Go and have the ECM setup for the proper size tires. You will need revolutions per mile, I think to recalibrate the speedo. This will need to be done at the dealership. Go have it setup properly and then tell us what your mileage is.

 

it may something to with the fact that he has a programmer on the highest setting with 35"tires. i have no programmer and 33" tires and i get between 18 and 20 mpg.

 

Couipole of questions. When you refer to "Flash" you refer to a program upgrade on the ECM or the computer?
I have run the truck without the chip installed and still get the same MPG. So, I figured might as well have the extra HP. I will call a dealership and see if they have any ideas. I will keep you informed.