new to group.
i just purchased a 7.3 excursion 4x4 had a 4 inch lift installed with 315x75x16 tires all stock to my knowledge. I have done the 6637 air filter and dropped my fuel tank replaced fuel filters.. problem is getting poor fuel mileage around 400 miles To a 44 gal tank. What can I do to increase mpg in town and while towing.... thanks

 

Smaller tires.

1. They kill fuel economy in stop/go and towing situations.
2. They make the odometer wrong.

 

What is the hand calculated mileage for highway and city or mixed?

Like Rich said, tires and lift kits are not helping you in anyway in the MPG department. You need to check the boots, up-pipes, etc... for leaks as they will rob you of power which in turn makes you put your foot further into the skinny pedal, which in turn decreases your MPG.

Also, it is an unwritten rule that you must post a picture of the new to you vehicle, we love pictures...

 

Poor alignment, dragging brakes, greaseable u-joints that need grease, any thing not right with the running gear can also cause lower mileage.


Biggest cause can often be a heavy throttle foot.


Welcome top FTE

 

400 miles to a tank IS decent mileage... You are not driving a Fuel efficient vehicle. Take all the suggestions above, and you can make small gains, people here are getting anywhere from 11 MPG to the elusive 19 MPG. You're in the Big Leagues now, Open your wallet and let it breathe....

 

"Let it breathe"... that just cracked me up.

I'm on mile 435 right now at 3/4 tank in winter 4X4 driving - but I don't have the monster 44-gallon tank. He can likely get more range on that tank if things are right.

 

Thank you, I'm here all Year...Coming from the designer of the WMD of Diesels, ( "The Buck$ooka") I consider that High praise. I know there are many out there that have squeezed every MPG out of their rigs, and every dollar out of their wallet... This hobby is not for the faint of Heart......

 

As mentioned the tire size will mess with your MPG ccalculations. You are going (much?) farther than you think on over sized tires. Best way to check is to use the mile markers along side of the highway. In Cali. at least, the white metal ones with the gold stripe across the top. They are surveyed and accurate to less than an inch. Can't put them in the middle of a cross street of course but you get the idea.

 

All of the above and...use GPS to calculate your actual mileage traveled.

 

What are your driving habits like? You might want to consider driving a little more conservatively. It is an 8000lb brick so mileage will never be overwhelming.

That being said you should drive slower if MPGs are a concern. I do about 1/2 freeway and 1/2 city streets. If I drive 65mph on the freeway I get about 14.5mpg overall and if I drive 75mph on the freeway I get 12.5 mpg overall. This is on my performance setting and still having fun on the city streets. Just that small change in my driving nets me 2mpg. If I were to always drive like I had 6 bails of hay in the bed then I'd be doing great...but that's not fun and, although it's no stop light to stop light sensation, I'm also not interested in getting passed by grandma doing 10mph UNDER the speed limit in her 1995 Chevy Corsica.

I'm not young so don't feel the need to get there 20 seconds earlier by driving like a maniac but I'm not the most defensive driver out there either. I made my compromise with top speed to gain some economy back to offset my off-road tires and city driving.

IMO each 7.3L seems to have its own personality. Whether it's just from the tolerances during manufacture I don't know but some guys seem to get good MPGs (like Sous who's in the higher teens), some get in the middle like me (I get about 14mpg), and others, no matter what they do, seem to be on the low end (11-12mpg). Just my .02

 

Just one thing to consider in the MPG debate is the fact that it is a pain in the rear to fill the tank to the same level every time without doin the Hutch/Harpoon mods. You can be as much as a couple of gallons (or more) off on each fill up without them, especially if you fill at different stations and/or pumps.

 

That's why I slowly top mine off till there is diesel at the filler neck, the only way to know I consistently fill the tank to the same level.

 

The harpoon mod will let you fill to the filler neck in less than a minute after first shutoff of the fuel nozzle. No more slow filling for 5 minutes. Highly recommend it when doing the hutch mod

 

+1, this was one of my favorite mods to my truck. I also took the time to widen the fill neck to allow for the "big truck" 1 inch pumps. Nothing like pulling into the Pilot/Flying J commercial truck area and filling up in 30 seconds...

 

Oh I plan on it when I find the time to do the list of mods I have the parts stacked up in my shed for (hutch is one of them!) how did you widen the neck? That is something that is of interest to me for sure!