Went on a trip to DC last week. Pretty much all Interstate, ran 65 to 75 mph.

I filled up before I left and reset the trip meter.
The low fuel light came on at 389.2 miles.
I filled up at 396.5 miles with 20.424 gallons.

That's 19.4 mpg, a new record for me.

I believe this truck is capable of 20 mpg at 55 mph.

 

I get average 17-18 mpg (imperial gallon) here in Canada but I have a fairly heavy foot. 3/4hwy, 1/4 city driving.

1998 4.6L v-8, automatic, 4x4, S/C,. 265/70/17 tires

Just installing 275/70/17 Wrangler AT/S tires, hope the mileage doesn't drop too much. May have to replace the speedo gear.

 

I'm not complaining either my 5.4 give 15 or 16 around town and about 19 on the highway so I am satisfied with that when you consider that these are full size, full frame pickups and not neons I think we're doing ok. I cruise at about 75+ on the highway but I dont mash it to get there let the truck take you up its got plenty of power.

 

I was averaging over 19 mpg until I started having problems with ignition wires, which will jam up the EGR passages. I mad an appointment at the dealer to have them cleaned, (1.5 hrs + gasket) so yesterday, I had a tech where I work put a scanner on it for the CEL and whaddaya think came up? EGR insufficient flow. Try using Amsoil PI, following the instructions and see what happens. I expect that once the EGR passages are cleaned, with my 285/65/R17 tires on the rear, that the mileage should be over 20. Should that occur, I'll put the chip back in and report.

 

I've got a 1998 supercab f150 4x2, with a 5.4 V8. It's a daily driver to and from work (17 traffic lights in 15 miles each way). I'm only getting 13 mpg. It does better on the highway, but I don't know the exact highway mpg.

 

The 17 traffic lights is killing your gas mileage.
To improve mpg I would recommend ignoring every other light.

I think a 15 mile commute with 7 or 8 traffic lights will show significant gains over what you're getting now.

Let me know how it turns out.

 

you have a 24.5 gal tank. same as me. My 98 5.4 4x4 lariat get 15.5 in a mix of short hwy and light to light driving. considering it weights 5120 lbs without me in it and a half tank of gas, it has a 330 cu V8, its 4 wd, has a towing package, etc.... its not bad, actually pretty dang good gas mileage. On a hundred mile stretch of 55 driving it got 20 mpg. It is a FULL SIZE 4X4 TRUCK. What did you expect gas mileage would be? Lets be realistic.

 

Raoul,

You truly are a man of extreme intellect and vision. I don't know why I never thought of that... Hell I may just run them all and join the 16-18 mpg club. What's a little sheet metal damage anyway.

You are the man.

 

Just got back from a 2500 mile round trip to Los Angeles. Took I-5 the whole way. Took it easy and averaged about 60-65mph most of the time. Ended up with a 15.9 mpg average. This did include miles while in LA and a moutain pass or two.

Overall, very impressed and satified with that. This was the first really long haul with the truck, and it was a very comfortable ride.

I put six cinder blocks in the bed, and that really helped smooth out the ride. When empty, it tends to "bounce" just a tad.

 

What a waste!
You could have hauled two Canadians to Disneyland, you know.

 

i have a screw 5.4lv8. i have put about 2500 miles on him. i average 13.28mpg. i added the K&N and a lid....if these things helped i don't think it did much and i do very little stop and go driving.....

 

Raoul:

Didn't think about that!! It has a soft tonneau cover too!! It would have been just like home for them in the back! Disneyland was a blast!! Felt just like a kid again!

Skagel:

Is that 2500 actual miles on your rig? If so, then it's probably still "breakn' in". Mine is now at 78k. Ran Texaco 87 octane the whole way (and have been since I've owned it). I have the K&N drop in, Gibson SS exhaust and the cover. Plus the extra weight of the bricks and the rest of the crap I hauled. The very best mpg between gas stops was 17.2 one time. The worst, 13.6.

 

MitchF150,
yeah 2,500 actuall miles....so are you saying i will get better mpg after he is finally broken in? and when is he finally broken in? the only extra weight i have is the ARE lid and the Stainless brush guard...i only weigh at most 125 myself so what should i try and shed some weight or is my mpg going to get any better.....

 

I get around 12 in the city and 15 on the highway and I have a 5.4. Oh well I still love it.

 

I'd say that you need to get about 10k on an engine/tranny for it to 'loosen up' some. Then you should start to see some increase in mileage. Don't expect more then 14-15 mpg average at best anyway. These are heavy rigs, and many other factors contribute to mileage..... Gears, terrain, driving habits, altitude, temp and on and on.

I'm averaging 14-15mpg with an empty truck with my day to day commuting (I push the scale to 200# myself! and could stand to lose 10 or so, but I digress).

You should only be concerned if you are only getting 10-11mpg with a stock truck. Then something maybe wrong.