MPG Help!

[RYAN SHAE]

I am very dissappointed with my truck. It is a 1 ton, long bed. 35" tires 6" lift. AFE intake and 5" straight pipe. It is not chipped or tuned. I have averaged out the past 2 tanks of fuel. And I mean tanks. From as full as you can get it til the fuel light comes on. The first time I had about 250 highway miles and the rest in town and the 2nd was all in town. I got 11.2 mpg on the 1st tank and 9.8 mpg on the 2nd. The only other difference between the 2 tanks is on the 2nd I had my exhaust on and I ran diesel kleen with it. I really need some help. Any info would be appreciated.

[kinghawg98]

tons depends on your driving style. Are your fuel filters clean? Is your air filter clean? Fluids good? tires aired properly (Obama says that's at least 2MPG or so..) I've heard a 5" pipe doesn't do good things for mileage, something about backpressure..

Other than that, get it tuned. I have 37s on a 6" and get 14 with mixed driving. less if pullin a trailer. slightly more if moderate speed on a hwy. best is 21 mpg, going 52 mph.

[RYAN SHAE]

I have a moderate foot. I have never raced it at all. It is current on oil change. I had the fuel tank drained and the fuel filters have been changed twice in the past 2500 miles. Air filter is clean, but it is a AFE oil filter. I might try and switch to a pro dry, but that shouldn't make that big of a difference, I don't think. I was told that a truck like mine, set up like mine is should get 12-14 in town and 16-18 on the highway. That would be fine. I sold my Dodge Hemi for this truck and I figured that if the mpg was comparable then I would alot rather drive the stroke, but this is just stupid. I may end up dropping it back to stock and sell the tires for some smaller and narrower tires just so this thing don't eat me alive. I am very dissappointed

[yosh30]

mine doesnt get the best either, driving 65-73 on the highway i average about 14.75..everything is current on it (oil change, fuel filters) all that good stuff..i was reading around and found this stuff called FPPF(you can find it at oriellys by the diesel kleen) and supposedly its supposed to work great..its around 6 or 7 a bottle, the bottle treats 4 tanks..but i just put my first little bit in the other day, ill post back in a week or so with some results..

[Stoker0560]

do either of you have your speedos corrected for the larger tires? Cuz if you dont youll be surprised the effect it actually has.. a 37" tires actually travels about 1.3 feet further per tire revolution than a stock which is about 32-33" diameter.. do the math..

1 mile 5280 ft
a 37" with a circum of 9.6ft would make 550 full revolutions in 1 mile
a 33" with a circum of 8.6ft would make 610 full revolutions in 1 mile
so if the truck thinks everytime a tire went around 610 revolutions that it traveled a mile but you really had 37" tires..you actually traveled a full 576 feet further per mile.. multiply that by 300 miles..thats 172800feet which is about
32 miles that your truck did not register that you actually traveled

so just for the heck of it beings ive already gone way overboard..if you got 300 miles to a 30gal tank..you got 10mpg...but if your truck didnt register 32 +- gallons..than you really got 332 miles to a 30 gal tank which is actually a full MPG better.. not much but makes a difference..

over the coarse of 100k miles on 37s your truck really has 110909 miles on it..


be easy on me, i'm really bored

[yosh30]

Originally Posted by Stoker0560

do either of you have your speedos corrected for the larger tires? Cuz if you dont youll be surprised the effect it actually has.. a 37" tires actually travels about 1.3 feet further per tire revolution than a stock which is about 32-33" diameter.. do the math..

1 mile 5280 ft
a 37" with a circum of 9.6ft would make 550 full revolutions in 1 mile
a 33" with a circum of 8.6ft would make 610 full revolutions in 1 mile
so if the truck thinks everytime a tire went around 610 revolutions that it traveled a mile but you really had 37" tires..you actually traveled a full 576 feet further per mile.. multiply that by 300 miles..thats 172800feet which is about
32 miles that your truck did not register that you actually traveled

so just for the heck of it beings ive already gone way overboard..if you got 300 miles to a 30gal tank..you got 10mpg...but if your truck didnt register 32 +- gallons..than you really got 332 miles to a 30 gal tank which is actually a full MPG better.. not much but makes a difference..

over the coarse of 100k miles on 37s your truck really has 110909 miles on it..


be easy on me, i'm really bored

yeah my speedometer and odometer is off, but i dont go off the odometer on my truck..i just calculate it out after i travel, like on google maps or whatever..how can i get everything calibrated back to normal?

[Stoker0560]

Im not sure how to do it, i think the dealer can program it in, i just bought a GPS for mine, 150 bucks, tells mileage MPH everything, its the most accurate for sure

[Foamy]

Ok this is going to sound very strange but here is my story. Every 3 weeks I drive from Edmonton to Kearl Lake(north of fort mc) and in the summer I was getting maybe 12-14mpg. I was talking a service manager at a dealership about maybe getting my lift taken off to try and improve my mileage. The guy told me before I go that far, to throw 500-800lbs of weight in the back and run some of the ctane booster that ford sells. Well I thought that was crazy but what the heck, I need the extra weight for winter so might as well try it a month or so ahead of time. Well aside from smoothing out the ride(I knew that would happen), I actually managed to get 17.6mpg on my last 2 trips with 800lbs of sand in the back. I had tried running that ctane booster before for a few months without any extra weight and didnt notice any increase.

I am a little confused about how this would actually work because everything in my mind is saying more weight = harder on the mileage. I am not saying this will work for you guys but it might be worth a shot? BTW I noticed about a 100° drop in egts after this too..and yes these are hand calculated numbers.

[kinghawg98]

i must say, that sounds.........implausible.

[Mike Hickman]

Send it to myth busters !!!!!!!!!!