I have spent a fair amount of time working on improving a cars MPG.

My current best car is a 03 Ford Explorer.

I love everything about it but its drinking problem…it is a bad drunk, it really drinks the juice. And it is so out of line I believe Ford and other car makers are cheating us.

Comparing the MPG reading of the 03 Ford Explorer to other cars SHOWS THAT IT IS VERY ODD and Very off.

I am talking testing by pure nonstop runs at speed with crust control reading by a Scan Gauge II.

These test show what my cars CAN do on a road trip.

I had a 2000 Mercury Grand Marques, (A Crown Vic in Mercury trim) it GOT at:

65MPH 29/30MPG @ 1700RPMs, and at 75MPG got 26MPG and at 85MPH got 24 MPG.

Basically the same engine, only 40HP Less and a 3:27 rear end of my Crown Vic.

My 03 Crown Vic, gets at 65 26MPG @1700RPMs and at 75 MPH gets 22MPG. Again the same progressive loss of MPG per each 10MPH faster, it has 240HP, same transmission and rear end of the 2000 Mercury.

The 03 Explorer has the same 4.6 V8 as the 03 Crown Vic, even with the same specs of 240HP,

and with its taller wheels has a final gear ratio of 3:50 VS 3:27.

And yet at 50MPH @ 1500RPMs gets 27/32MPG…all very good…

BUT go to 60 MPG and 1800RPMs and it MPG drops like a rock to ONLY 18MPG, and it only drops a MPG for each 10MPH faster…

That is at around 55MPH the MPG DROPS to 18/19MPG, it has to be programed to do that…then for EACH 10MPH faster it THEN only drops 1MPG…

So once it has taken all the MPG away it then losses 1 MPG per 10MPH so even at 80MPH it still gets 16MPG.

EVERY Car I have tested this NOT normal!

Every CAR has the same progressive or slowly dropping MPG.

At 50 MPH you get a good MPG, and as you speed up the MPG SLOWLY drops, like the 2000 Mercury went from 32MPG at 50 MPH and for each 10MPH it dropped one or two MPG so 60 was 30MPG and 70 was 28 MPG and 80 was 26 MPG and 85 was 24/25MPG.

EVERY Truck, well SUV and Van I have tested has this odd fixed MPG readings.. A 02 Explorer, 03 Explorer: Go faster that 55MPH and BLAM 18/19MPG and my 93 Chevy Van also got only 14MPG at 65 to 85 MPH running a Van’s standard 3:43 rear end.

I rarely checked my 74 and 78 Chevy vans, but they with NO overdrive and a standard 3:43 rear end, running carbs got a similar progressive drop in MPG from 15/16 at 65MPH to mainly 13MPG at 75/80MPH.

So historically Vans and trucks got crappy MPG so the stage was/is set for modern Vans and SUVs to do so too…

We are told that a BOX cannot go through the air…

The 2003 Ford Explorer has a drag coefficient of .41 Cd.

The 2003 Ford Crown Vic has a drag coefficient of .37 Cd.

So it is easy to do a fix so that these newer FI computer controlled overdrive SUVs and Vans, and Trucks so that they will get their historically bad MPG.

I THINK IF I can find someone to program the fuel tables from say a 03 Crown Vic my/your Explorers will then get the same kind of MPG the Vic does.

So I am looking for a tuner to do this.

OR help to learn to do it my self.

Rich

 

There is more to it than shape of the vehicle. It includes weight, angle of the windshield, other protrusions, (mirrors, roof rack, etc) and most important, the turbulence created under the vehicle. That's why super high performance cars sit on the ground and have full belly pans.

 

Also don't forget the extra powertrain losses due to 4WD/AWD. I'm not sure if similar fuel economy numbers are available between a RWD Explorer, and AWD Explorer, and a 4WD Explorer, but I suspect each of those are different as well. And rolling resistance of the tires.

-Rod

 

Keep in mind that the speedometers and subsequently the odometer are not all that accurate. Each vehicle that you are comparing should have been calibrated with GPS to ensure that the MPG you are looking at is reality. So if your current explorer is running a little fast, it will show more miles driven than a spedometer that is running slow, which will use the same fuel over the actual distance, but will read out as different number of miles on the odometer. Even the Scan gauge can't compensate for this unless you have a GPS adapter for speed or distance. My current 2013 F150 runs fast, so at 63 showing on the speedometer, i'm actually only going 60 mph in actual velocity, so its racking up miles that I'm not actually putting on the vehicle which skews the MPG calcs. Basically before you get too frustrated with the MPG you are getting, make sure that is actually the real number before you start chasing something that might be corrected with a calibration.

 

There is no reason for automakers to “program” lower MPGs into heavier vehicles.

CAFE requirements dictate that they try to do anything BUT that or they pay out the wazoo in taxes to the gubmint as a result. Stockholders don’t like that.