REALLY lousy gas mileage?

[IndyExpedition]

I have a 2000 XLT 4x4 with the 4.6 v8. I know this isn't a fuel efficient vehicle...but what kind of gas mileage should I really get? I 've changed out the exhaust (new flowmaster 40 series system) and a K&N filter smf hope to add a chip to it but the mileage seems like it's alot less than everyone elses on here! I get 12 in the city and 15 on the highway. I ran 87 octane gas and the truck ran horrible, rough, misfired, and had no power. I get gas at a Sams Club so premium is cheaper than 87-89 octane everywhere else. I've also had a bunch of maintenance done on this truck in case the previous owner didn't keep up. I've owned this truck since last May. Transmission service, transfer case, oil change (all synthetic) and even a fuel filter recently. I don't know that it's been tuned up and have about 95k miles on it. I actually try to keep my foot out of it. Does my truck just run that lousy or is there something I need checked? I figured when I bought the truck that 13-15 mpg was about normal. But how would someone with the 5.4 get better than mileage than me? Any ideas or suggestions are appreciated!
Thanks!:troll:

 

[ELVATO]

I have a 2003 4.6 and if it makes you feel any better, I get between 12-13 in the city. This is with a CAI and a tune. Then again, I ride hard. I usually keep my foot in "it". I think I'm going to need another set of brakes soon

 

[green03]

Hey ELVATO,
How's that custom sniper tune working for you? You have been awefully quiet lately...........

 

[lakmflx]

Matt did i ever send you my computer code? cant remember....

 

[green03]

Was it a ZUT2 or ZUT3? I have better info now on what I need?

 

[lakmflx]

Ill run out to the truck real quick and look ... cant remember either LOL


Well shit nvm wife has it today :shootout:


Ill PM you later with it

 

[ELVATO]

Originally posted by green03
Hey ELVATO,
How's that custom sniper tune working for you? You have been awefully quiet lately...........

Excellent Oh yea, was able to hit 110 when going down a slight downhill. Don't worry guys, it was at night, when there wasn't much traffic

 

[03ddie]

Originally posted by ELVATO
Excellent Oh yea, was able to hit 110 when going down a slight downhill. Don't worry guys, it was at night, when there wasn't much traffic

How much does that cost and what will it do?

 

[ELVATO]

Originally posted by 03ddie
How much does that cost and what will it do?

It was a custom tune from Green03 using the Sniper Tuning.

Really improves shifting

Send him a PM, I'm sure he'll hook you up.