suprised at mpg in high mile 5.0 ....

[pwrshft99]

I have had quite a few 5.0 mustangs and have a 4.6 GT now. I don't think any of them can match what my new truck has been doing.

It's a 2000 explorer limited, I drive the same 175 mile drive once a week. My first trip got me 19.7 mpg with 89 octane Mobil fuel. I was pretty happy with that considering the 154,000 miles.

Before my next trip I was going to change the plugs but found new boush platinum 4 pronged plugs had been installed with new wires, kool.
I then removed the stock air box and ground the flange off the plastic mass air meter housing. This allowed me to clamp on a high flow filter. The only other change was raise tire pressure to 38psi at all four corners. Well I did use 89 octane gas from Murphy Usa.

This time it averaged 23.5 mpg !! The weather condition were comparable as was driving style, I'm guilty of drafting semis where ever possible lol.

Truck is completely stock with Walmart high mileage oil. I'm looking into an electric fan and maybe a few other things to squeeze a few more mpg..

 

[Joe Dirt]

That's pretty good!

But, those Bosch plugs will not be your friend for long... Search Bosch plugs on the forum...

Also, the tuning in the truck is for 87 octane, running 89 won't net you anything performance wise besides spending more $$$.

Are you doing miles driven/gallons refilled with?

After you changed your filter setup, did you reset the ECM?

 

[pwrshft99]

I did disconnect the battery because I was messing with the stereo. I had some autolite double platniums to go in but these were so new, maybe ill change them before fall.

I did a shorter highway drive of about 100 miles on 87 octane and couldn't break 19mpg this was after my first trip but before the second.

Truthfully I was going off the display in the console. Im sure its not completely accurate but I should atleast be able to use it figure average gains and losses.

 

[techieman33]

Seriously get rid of those bosch plugs asap. And yeah the mileage can be pretty good if driven carefully. My personal best was 24.3mpg, never managed to repeat it though.

 

[Joe Dirt]

Yeah, the display is iffy, but I'm sure you're doing well... Do a miles traveled vs. fillup soon- I'd be interested in what you've got running- you might have a factory freak!

My uncle had a 1999 V8 bone stock AWD with 3.73's that netted 26-28 on decent highway trips... <- Factory freak!

 

[pwrshft99]

That's awesome mileage, I was wondering what gearing I have..

I was driving an auto SHO that's was getting 28+ mpg at bout 80 mph lol, was worried the truck was gonna get 15 like the mustangs did.

 

[Joe Dirt]

Your Mustang (at least a Fox Body) should have gotten a lot better- all of our Mustang group around here was getting 22-26 in ours... My best SHO mileage- 35mpg on one trip up north, 304 miles. '95 MTX...

You've probably got 3.73's, the axle code is on the door jamb. Some had 4:10's as a tow package...

 

[damarble]

I didn't realize 150k was considered high mileage anymore. It's just barely broken in by 100k! Then again I'm used to driving 200k+ cars and never having issues...

My best SHO mileage- 35mpg on one trip up north, 304 miles. '95 MTX...

Damn, the best I've squeezed from my 91 MTX has been 29, that's after fixing the O2 sensor that got me 25 and under for a long time.

 

[mattlws6]

Thats doing good on milage for 154k man not gonna lie. I would reccomend taking the Bosch plugs out as well. I had fouled plugs after 1 week running them. I figured I would replace them all before they failed on me 1 by 1.