hey guys,

just noticed while at the dealer's lot today that the new '03 5.4l 4x4 equipped s-crew is rated at 18 mpg on the highway...up one from '02. plus the 3.73 axle now appears to be standard. kinda odd that highway mileage would increase with shorter gearing...isn't it??

 

Troy,

That's correct, the mileage almost has to be less, not more. However, that's assuming that nothing else changed and it's very possible that they changed the effeiency of the truck somehow:

1. New code for engine computer controls
2. Less friction somewhere
3. Better exhaust system, etc.

The actual difference in engine RPMs should follow this rule from a 3.55:1 to a 3.73:1 gear ration.

((3.73-3.55)/3.55)*100% = 5.07% increase in engine RPMs.

If the mileage increased from 17 to 18, that'd be an increase of (18-17)/17)*100% = 5.88%

So, in order to acheive a 5.88% increase in mileage and a 5.07% increase in engine RPMs, they'd need a 10.95% increase in efficiency which would seem hard to acheive IMHO.

Now you've got me thinking...How'd they do that...Maybe someone goofed and it was supposed to read roughly 5% less mileage, not more...hmmm

~DM~

 

Check to see if the rules of the game have changed (like: perhaps they now considering "Highway Speeds" to be 50 MPH instead of 65)?

 

i have no idea what speed highway mileage is based on...anyone know? however, that said, i have my doubts that it was ever 65 mph...i'm betting it's pretty much been based on 55 mph.

if my truck ever got 17 mpg while going 65 i'd crap my pants...!!!!

 

daveman,

i wonder if maybe they changed the 4r70w's overdrive ratio...?

 

I was thinking the same thing as Troy, maybe they changed something in the tranny to balance out the lower ratio rear end. *shrug* I do remember reading somewhere that there was a new and improved tranny on the drawing boards for some sort of Ford vehicle aplication. Maybe the f-150 is the reciever of the upgrade. *scratching head*

 

viper,

i know for the '04 model year the 4r70w gets upgraded to 4r75w and the 4r100 is replaced by the 5r110 (5 speed automatic). but, i don't think there were any major upgrades for '03...fwiw.

it remains a mystery...altho i did notice that the dodges have also gained a 1 mpg on the highway loop...so maybe the way the epa calculates or tests for mpg has changed...? i have to check and see if the chebbies have also increased...

 

Troy,

I just emailed you a copy of the 2003 marketing strategy PDF document and according to the fuel mileage ratings, the 4.6L in a 4x4 gets the 18MPG, are you sure you were looking at the correct specs on the window sticker while at the dealer? Maybe you were looking at the standard ratings and if the truck gets a 5.4L engine then the ratings should be the 17 MPG you alluded to earlier.

I dunno...

~DM~

 

for those interested...

tonight i headed back to the local dealership to make sure i wasn't seeing things. and yes, the 5.4l equipped 4x4 '03 s-crew is rated 18 mpg on the highway...with the 3.73 rear end. local dealership currently does not have any 4.6l equipped s-crews, but according to data on the internet, the 4.6l 4x4 s-crew's highway rating is 19 mpg for '03.

so, it remains a mystery as to how ford eeked out another mpg over the '02s...

troy

 

on the trip down to Kentucky I averaged 16mpg....I thought it was wrong since I never get more then 13/14mpg.....man and I thought I was doing good.....well, I didn't drive the truck Steve did.....hmmmm maybe it is my driving then

 

Something as simple as a different muffler supplier to a different gasoline supplier, in my honest opinion, could have swayed the efficiency a mere 1 mpg. So many things are involved in the efficiency of a vehicle. It's super hard to say. They could've just changed oil suppliers for the stock oil out of the factory.... Just thinking out loud here.

One thing is for sure. All of the vehicle manufacturers are striving to get as efficient as they possibly can and, when they can tack an extra 1 mpg (even if it came down to decimal places) on to the fuel economy of the vehicle, they're going to do it. There is a reason we all have a Low Emissions sticker on the side window. They all want to show off that they are at least 'thinking' about environmental issues that are high on the public's minds (ie. Clean Air)...A simple sticker on a window saying "LOW EMISSIONS" might sway an environmentally savvy buyer to go with a particular vehicle.

Again, just thinking out loud. I do have to agree with you though Troy. It is curious where the extra 1mpg came from.

RP

 

Not abnormal... I was averaging 14 overall, but got 17 to and from the canoe trip and sand dunes 2 weekends in a row... mainl freeway, lots of cruise control, and few hills (all this was also with a loaded bed full of gear).

-Joe-

 

the material in the '03 catalytic converters has changed....less platinum is being used now....why......don't get me started Fords metals departments analyst just **** me off....

 

do any of you keep the lifetime milage averages on your vehicles or are you just reporting individual fill-ups as tank to tank depending on how you fill it up, the nozzel and the angle of the truck will vary the numbers greatly.

 

yes I do......I have graphs & charts...cost of the gas where I bought the gas, what time of day it was, what day it was, how much gas was put it at each fill-up and I always fill the tank.....etc, etc. etc....