I get 14-17. The only real thing I've done that made a noticeable improvement was putting in Denso Iridium plugs. They help a little bit. 1 mpg I think. I maintain my truck pretty good so I think 17 on the freeway is the best its ever going to get.

 

I get 15.5-16 mixed/17 highway with dog **** winter blend fuel, and 17-17.5 mixed/18-20 highway with summer blend.

'98 4.6 2WD, 3.55's stock tires CAI, pulleys and synthetic from front to back.

I'm trying to figure out what will give me the most bang for buck on a limited budget; Magnaflow or Gibson cat backs, E-fan or a tune. I can only swing one.

 

E-Fan will help the most... The factory fan will still be pulling air even at highway speeds....

 

Was the truck throwing a check engine light or did you just replace them?

 

Yea, same here 16 mpg after Denso's. I'll take it lol. I tried Borg Warner Brand O2 sensors once and couldn't get better than 9 mpg. Those came back out after the second tank. I didn't notice it running any different, just the gas gauge sinking faster than usual.

 

I just got 17.4mpg today driving 260 miles goin around 65-70Mph and drafting behind bigrigs :lol

 

2002 5.4L 125,xxx miles on 33's
15mpg no matter what

 

99, 4.2L V6, 5 speed with 211,262 miles, extended cab, short bed

About 12-15 in town, generally on the lower end of the spectrum.. 19-20 on the thruway consistently.

 

10mpg if im lucky with a 6' lift and 35" tires. 4.6l engine

 

99 4.6 4wd
12-14 city 15-16 highway

 

2003 supercrew 5.4l 3.73 ls 4x4 13k miles

i have the scanguage2 installed so i can moniter the MPG.

pretty consistant i have been getting 17.0 - 17.6 mixed. i think i could hit 20 if the tank was all highway.. i drive it pretty easy with slow starts and a fair bit of coasting to stoplights etc. watching the scangauge really teaches you how you are burning fuel and when.

 

You might want to look into some different gears my friend.

 

You know you have to calibrate the scangauge right?

 

yes i calibrated it., and i have been double checking with good old math

 

I pretty consistently get highway 14.5 - 14.7 mpg in a bone stock 03 scab 4x4 5.4L on 265/70/17's AT tread

I bought pipe and coupler today to do the gotts mod, so it'll be interesting to see how much it changes.