I propose an experiment for all 4.2/3.8 Ford 150 operators. I would like a few people to fill their tank full, and drive 1000 miles, filling as necessary (record gallon total) and then filling at 1000 miles. Then divide total fuel gallons into 1000 miles to determine an overall mileage. Numbers will vary as some drivers will be over the road more than others and some will be in tight traffic but the results will be realistic everyday fuel use. Post your results, describe your vehicle and generally your driving conditions and weather. I hope several will participate. Thank you.

Im about 500 miles into the experiment.

 

I've recorded every fill (miles driven, gallons filled) in my phone/ppc since july/07. Which includes about a year living in the city and the recent year of country.

So starting with living in the city... daily commute about 2mi (35mph) streets and 7mi highway 65mph (one way, so x2 for round trip) plus of course the trips to the grocery store, lowes, sitter, etc mostly add to city milleage.
Example summer MPG: 14.82, 14.14, 14.17, 14.79
winter MPG: 13.16, 12.08, 13.04, 13.10

And now since living in the county... daily commute is 7.5mi county road (55mph) 30mi highway (65mph) and 1mi city (35mph) one way so round trip about 80mi.
Summer MPG: 17.38, 17.37, 17.33, 17.37, 17.26 (these are all consecutive too btw)
Winter MPG: 14.20, 15.49, 14.91, 15.42, 14.42

Vehicle specs: 99 F150 4x4 4.2L, 5 speed manual, reg cab, short bed, open diffs unk ratio, 285x75r16 Kuhmo MTs (33", speedo corrected) on AR cheapie aluminums, low profile cap, 2" diy lift (cranked torsions, replaced rear blocks with 4" total), think that about covers it.

Overall not really impressed with the mpg of the v6. Most v8's achieve this or better. And contrary to popular beleif those 'huge' 33's didnt hardly effect my numbers (less than .5mpg change) compared to the 265 at's that came on it (i beleive because the contact patch with the road is about the same since the actual tread runs wider on the at's than the mt's so they end up being the same width in reality).

 

I already have plenty of data. My week is mostly local with usually 2 highway trips about 30 miles round trip. I have it tested out with several fuels. Best Avg with 87 is 13.51. Avg with Sunoco 89 is 15.06 but it does improve some with different driving conditions up to around 17. I also have it figured out that it saves me .5 to 2.5 cents per mile to run the Sunoco 89 over the other fuels. BP 89 is not as good and the 87 is not good for me at all.

 

Hi big and dave, ty response.
I got 18 mpg over 1000 miles, paved all, half city and half hiway. I drive a 2007 reg cab, 5 speed, 4.2, 3.30 gears. I will next try to run 91 octane gas presently im using 87.

 

Last 2 fillups of Sunoco 89 for me were 16.2 and 16.4, that's a fair mix of local and highway. Mine's an auto, clutch is always better too.

 

Best I've ever had is just over 14 that was all highway (Dallas to Louisville). This was just after new plugs/wires, new air filter, oil change etc.