I made a trip to Detroit yesterday from grand rapids,MI bout 350 miles round trip and got 17.5 mpg. I cruised on average bout 80 sometimes cruising for a little bit at 85. Drove w/ the tailgate down the whole way. I figure thats pretty good milage for how fast I drove

Matt

 

I get 14 in the city and 19 on the highway.I also drive around 75-85 mph on the highway with the a/c on.

 

I was very dissapointed with milleage when I first got my truck ('99 f-150 4.2L 5speed reg. cab short bed 4x4). I figured it was the smallest and lightest full size truck from ford (all except for the 4x4). I was getting about 13.5 city / 15 highway. But several things I found out helped milleage. For one, driving slower helped. Second, I shifted at a much higher RPM than the 4.9L inline 6 I was used to driving, and shifting at higher rpm actually got me better milleage (the 4.2L just doesnt have enough grunt to shift low like the 4.9 could), and the biggest thing was to leave the air setting on vent because it seems like the A/C pump runs on most of the other settings. It also seems I got better milleage with my cap off, even though its a low profile (doesnt stick up higher than the cab). SO now I get about 15.5 city / 17.5 highway average. I also got the bigger tires if that makes any difference, there the 275 65 or something like that. But overall, I am dissapointed with the fuel economy. My brother in law gets almost 15 mpg with is 460 dually and he drives like a maniac (well thats assuming he is calculating his mpg corectly lol).

 

I recently went camping and got 12.5 MPG while driving 80 MPH. Family of 5 in cab, bed loaded with gear, towing a camper and A/C on. I thought that was pretty good. I recently changed the engine fan out to a flex-a-lite dual electric fan kit, maybe that helped.

 

I got 17mpg with about 1/2 ton of rock on a 3hr drive... but I only went about 55mph. Even though 12.5 might seem good to some who have driven the 4.2's think about this... I a native to the 335 series engine forum (351C, 351M, 400) because of my other trucks, and a fellow I have chatted with alot has a holley fuel injection kit on a '79 f-250 with a 400 motor, c6 tranny, 4.10 gears and big tires (think they were 38's) and he gets 14-15mpg in the city loaded or unloaded... and he's pushing well over 300 horse. When I think about my little 4.2, I get sick lol! Not that I dont like the little guy though! Just food for thought...

 

My original mileage was 13 in-town and 16 on the highway. I added a soft tonneau cover, and my highway mileage went up to consistent 18. With my 3.73 gears, I get my best mileage with 800-1000 lbs in the back, usually 17.5-19.0. My absolute best was in November 2001, driving through the mountains in Tennessee and North Carolina, with my cover on and 500 lbs in the back, it was 20.1.

 

my 2000 f150 4.2 gets about 18 to 20 mile per gal. with an average speed of 75 to 80 i took my tail gate off and put a new air filter in and that made the big differance i also have a 5 speed so that helps

 

with a tonau cover lowered 2/4inches and 400lbs in bed on recent trip to fl from nc avg 26 mpg honest!!!now around town 14 or so i have chip,intake,exh,fans and 3.55 gears.

 

Wow that is good. My record to date is 18.9 But I think 4wd and the extra couple inches of ride hiegth hurts me, along with the bigger 265/75 tires. I do have a 5spd, and never use a/c. Didnt notice mutch difference between cap on/off but then again driving conditions werent exactly the same either. But I have noticed a big jump when you dont go past 65mph. When I drove about 70-75 mph my mpg would be down to around 15.5-16 (again the 4wd ride hieght probably creates extra drag the faster you go), I suppose a lowered 2wd would really have much less drag at speed 70mph+ but myself the 4wd is much more usefull than the extra milleage. Wish I could have both!

 

I'm not quite sure what was done to my truck before I got it but I'm getting around 21mph city and for some reason I get LOWER on interstate. It makes no sense to me, so maybe a sensor is off or something...

 

my truck is completly stock and gets 21 mpg on highway giong 80. i guess i just wanted to let you guys know

 

I'm getting 13.4 out of a 03 4.2 with 1500 miles. That did include towing a boat for 100 miles.

 

2000 F150 - /2wd/ reg cab / short bed / 4.2 / 5 speed / 3.55's w/ trackloc / 255/70/16's / toolbox / no tonoue cover / tailgate always on.

I consistently get 22 mpg out on the highway. I travel from NJ to either Boston, Rochester, Albany, Conneticut, South PA and Delaware almost every week for work.

Almost all travel is on interstate highways going anywhere from 65 to 75.

I purchased the truck used w/ 30,000 miles on it and it has surpassed all of my expectations.

I had driven my lifted Jeep for so long, I forgot that a vehical could get more than 8 to 10 mpg...