7.3 fuel mileage question

[bartman]

I know our engines are slightly different but I hand calc about 15-16 city and 19-20 highway. I hope it is just your tires and the calibration like Tbar said.

Me, too, but I don't see being that lucky.

 

[bartman]

I get an overall of 20-21mpg combination highway and city empty. Pulling 10,000 lbs of 5th wheel I get between 11 and 12mpg. My truck is bone stock except for the K&N air filter.

That's just braggin' right there.

 

[fgtex]

mpg's

Have you changed the fuel filter recently? I have only been around diesels for a short time and have learned alot from these forums. I noticed my mileage decreasing at a steady rate. From about 15 to 11mpf. After the fuel filter change I am in the 16 to 17mpg range (60% city / 40% hwy) for my daily commute. Truck is bone stock.

Like was mentioned before, check your speedo calibration. GPS is great!

fgtex

 

[bartman]

Just my .02 but the most MPG gains I've seen on mine was from eliminateing AIR from the fuel and basicly, Tweaking the fuel system.

From the Tank..... The In Tank Mods, Then a Dahl 100, pre pump filter, then the Pre pump Mod, then the FPR smimmed to 70 psi.

My 2K got 13 to 15 MPG. After doing the above, I get about 16 to 18, unloaded... 10 to 12 towing my FW. ALL of my MPG checks are done, at the pump, doing guzinta math. Could maybe be a bit better... I've never re-cal'd my speedo from going to, 235s from, 215s.

The Intake, WW, exhaust mods, and the Q-zilla in the 75hp setting gave it more power & performance, but the fuel system mods is were where I saw mpg improvements.



JOE

Looks like fuel system is next.

 

[bartman]

Have you changed the fuel filter recently? I have only been around diesels for a short time and have learned alot from these forums. I noticed my mileage decreasing at a steady rate. From about 15 to 11mpf. After the fuel filter change I am in the 16 to 17mpg range (60% city / 40% hwy) for my daily commute. Truck is bone stock.

Like was mentioned before, check your speedo calibration. GPS is great!

fgtex

Fuel filter was changed within a few weeks of purchasing the truck. I'd love a GPS but for now, I'd just like to see more than 12MPG

 

[Crusin350]

From what I can determine, the 35's are 10% taller than the stockers. In that case wouldn't my results only be off by 10%?

The diameter of a 31" tire is 97.34", a 35" tire is 109.9". 11.4% diff. So if your getting 12 mpg you should increase that by 11.4% and get your actual milage, which would be around 13.36. which is a little better
I dont pull anything with my truck and I can range anywhere between 13 and 15 mpg (with a heavy foot!).

 

[bartman]

Ok, I'll take 13.36, but I am still curious how some are pulling in 16 or so with some of the same mods that I have on duallys no less. Could a loose converter in the 4r100 cause poor economy? I am not as familiar with the feel of an auto as I am a manual, so I don't know if my converter is loose, but it seems to jump to 2500 rpms with every push of the throttle.

 

[bad_bad_bubba]

SOme of it could have to do with genaral driving habits.

 

[bartman]

I drive like my grandpa


















When he was young

 

[1Wild Bill]

7.3 fuel mileage

If you have not already don it you need to have the computer recalibrated to match the 35" tires. The larger radius means your odometer is showing less miles than what you have traveled thus screwing up your mpg calculations.


Tbar

Would I need to have a local diesel shop recal my computer for my different size tires? My truck seems to be off by about .2 miles for every mile according to the highway markers (if those have any accuracy). And, my mileage is only about 12 too. Thanks--