run an identical vehicle with 400 lbs in the bed then run same vehicle with that same weight in "wheels and tires" and see what happens to your mpgs

 

I guess I don't feel too bad with 19.33mpg on an 1600+ mile round trip to Georgia and back this Turkey Day. I have clocked 20 in the past and have since added an Undercover Tonneau cover, but there was no improvement in mpg with the cover on.
My truck is an 07 SCREW 6.5' bed and I believer 3.55 rear.

 

well then my truck must SUCK!!! or i just need to give it more TLC to get it running better...

i'm only getting about 10mpgs...i think! i have a 1980 f150 lariat with dual tanks. I'm only running off the rear tank and the gauge doesn't work. so i can only guess what i'm running right now...

 

Steady state speed on the hwy any extra rotating mass in the wheels will not make a significant difference in MPG because once the weight is rotating it does not take any significant extra energy to keep it rotating.

Of course heavier wheels can often mean bigger tires in which case you will have aerodynamic losses and very likely higher rolling resistance. This is where the HWY MPG is impacted substantially from larger/heavier tires, not because of the extra rotating mass. In stop and go traffic the larger rotating mass will have a very significant effect and that effect is in addition to the higher rolling resistance and (to a much lesser degree at slow speeds) the poorer aerodynamics.

 

heavier wheels and tires- will put less power to the ground, now if you need less power to maintain 65, then how?

 

Because a heavier wheel (all other things equal) only puts less power to the ground when accelerating. If you are maintaining a steady speed the power output is the same.

 

where in God's green earth do you get your info from, the right wingists?

 

appreciate ya'll hijacking my thread guys!--Thanks-----DirtySCREW

 

You know - by the time you get done spending money trying to squeeze more mileage out of that thing, you could have bought a LOT of gas...........

 

yep. Most 5.4 4x4 f-150's get 15-16 mpg. Getting them to do better costs more then its worth solely for the MPG increases..

 

I'm trying to understand why you would be complaining.

You post up a message on the board with details on your setup, you state your MPG seems low and you ask for assistance as to why this might be.

A helpful fellow suggests maybe it has something to do with tires/wheels and that a heavier wheel will consume more gas. Another says this is primarily true for stop-n-go, not steady state driving. A short discussion ensues.

You return with sarcastic criticism for those attempting to help.

That is not a good way to encourage feedback next time you have a question.

I hope you figure out your fuel consumption problem. In my experience mods that are widely reported to save MPG over the stock setup rarely have the expected effect and a number of mods actually significantly reduce the range of your tank over a bone stock setup. But the aftermarket makers of these products love to brag about the increased MPG you can expect and there will always be a few jokers who are willing to testify how much better their MPG is over stock even when most people experience a slight decline. Then the usual excuse is something along the lines of "the dang thing is sooo much more powerful, I just can't keep my foot out of it".

 

Real---it seemed to ME that you and Openclass got into a pissing contest over wheel/tires. To ME it did NOT contribute to the thread or help the original poster--ME. If anything it was starting a flame war.

I feel that too many times there are ones who are genuinely trying to help out the OP but for whatever reason get sidetracked because someone insulted THEIR reply or got their goat. Then the sidetrack flame war begins.

Secondly, I along with probably 85% of people on this forum know about the differences wheels/tires can make. I have said repeatedly that I have Stock FX4 wheels and have 265-70R17 BFG ATs, which are stock size. Yes I know I may get a tad better mileage with a different tire with a different tread pattern. These tires are fairly new and were on the truck when I bought it; so that will be a while down the road.

Third, what's wrong with wanting to get the maximum miles per gallon?? I look at it as a challenge and sort of hobby. I feel that I should be able to get what my 2wd Yukon got. I find it as a challenge to see what can be done to my Ford to equal what my old GMC did. I feel if one car manufactuer can do it the other one can. I may be wrong, but it doesn't hurt trying. I like seeing what worked for one person and others and applying it to my vehicle to see if I can get better mileage.

You may not see any sense to my "madness" but I don't see the point of buying a Ferrai and driving in a 35 MPH zone either.

Real I'm not starting anything with you or any one else on this forum. I'm just saying lets stay on topic and help the OP as much as we can--WHETHER its me or someone else!!

Obviously trucks get different mileages for various reasons. I'm sure we could have a controlled environment with identical trucks and they would still get different MPGs for various differences in the manufacturing process. I look at it as if one F150 in a very similiar terrain can get close to 20 Mpgs, why can't I with my truck.

I APPRECIATE EVERYONES INPUT AND WELCOME ALL RESPONSES TO HELP US ALL MAXAMIZE OUR MILEAGE---DirtySCREW

 

Have you replaced the suspension? Done the factory maintenance?
I replaced the entire ORIGINAL suspension on my 2000 Super Cab F150 at 121K and picked up a solid 1.1 mpg all around, not to mention another 10k on my tires lol.
I see you have an FX4. Check your records and see where you are at maintenance wise.
I drove my previous F150 for 7 years. I had the 4.6L and a 3.08 rear
While I could nail 20.1 +/- on the freeways at 70, around town was a avgd. 14-15. I ran 265/75/r16 which were over sized compared to the OEM 235s I believe. I had the K&N with the gotts intake, hypertech canned tunes and gibson SI/SO 3" cat back exhaust. She was a dog around town but ran like a train on the freeway and had no problem burying the speedo shocking many a 5.4. But she was not quick. My 2007 5.4L 3.73 gets a solid 16.1 around town and 20.1 at 68mph. I run the OEM 18" good years now. This scalded dog will turn sideways in the light rain if you punch it. You should verify your current tire size. Being over the OEM can drop your fuel mileage substantially (10 to 15% and keep in mind 99.9 percent of statistics are made up on the spot).

 

malexander52---this is VERY interesting. I wouldn't think suspension would do ANYTHING unless there was some type of weight reduction. I don't have a clue where I am maintence wise except for what I've done:
complete brake job---(new wagner pads, rotors all the way around)
fuel filter
MC sparkplugs
K&N cone filter
oil change (MC synblend 5w-20 oil/ MC filter)

I would be estatic to get the MPGs you are achieving!!! I understand city driving will suck and be anywhere from 12-15. But I'm confused as to the highway mileage being so low on my truck. I don't have excess weight. I use cruise set at 70 MPH. I've set some at 65MPh (doesn't seem to matter much). I have properly inflated OEM size tires (265-70R17). I have factory wheels. I even have exhaust (Magnaflow 14' SIDO) to help. I've ran techron thru a tank. I do have the 3.73 LS gears.
My next step is to change ALL fluids throught to synthetic: trans, diffs, transfer case.
---DirtySCREW

 

Screw,

I hope you will someday (soon hopefully) find your MPG's your looking for. While I don't really have much to offer I just wanted to share my 03 screw experience with you. I had an 03 screw with the 4.6 2WD that only averaged what you are withthe 5.4 and 4WD. I took it back to the ford house repeatedly complaining how terrible it was with fuel mileage and was pretty much told that some trucks even though equiped with the same set up just dont put out the numbers that others do. I sold it with less that 30,000 miles and three years of owning it. Everybody else I new with the same set up was getting 19-20 mpg's. I just couldn't figure it out. I have since gone through 2 other fords and currently back in one that is getting no better fuel mileage than what you are now. It is basically what you have but an 07. I dont expect to get any more mpg's than what I currently get. I do hope you find what your looking for.

I know my post may seem pointless but it appears that some trucks just want do what others will even if they appear equal.