chucke311

What is the average is every one getting on there 5.4L 3 valve V8'S? I just bought a 2004 F150 SuperCrew Lariat Edition. Bone stock. I read online before I bought that average is 13-14 around town and 17-18 highway, anyone getting that? I live in Utah and we have up and down winters. So I know doing the warm up every day eats some of it, but on average right now(jan.) I'm getting 11 mpg. I run high octane, and I have 64,000 on it. Like I said just bought it and havent done a tune up really. And I notice the other day my truck when first started(or warming up) the exhaust had an egg smell, so Im assuming the cats are going out? Any thoughts would be nice, and be gentle I'm normally not a Ford fan but I read really good reviews on this truck and the styling is just to classy. Thanks people for any suggestions.

Lenn

I average about 14.1-14.5 city/highway. If I'm on the highway, I'm doing 80 and in town- I don't beat by any stretch of the imagination but I do like hearing the 5.4 purr. My truck is 2WD and stock Supercab.

ALSO- my truck gets reduced fuel economy when I run 91 octane. I thought it was just my imagination or maybe I was just driving it different because I had 91 in it and it felt peppier, but I had my wife burn thru a tank and it also averaged about 12.3 then.

As far as your cats, don't worry about them. I have yet to read someone who had to replace them at 64k due to breakdown. If you just got the truck, try to put the same grade fuel in it all the time and if you want to be really squirrelly, use the same station each time. You sometimes will get that smell when a vehicle ages if the owner constantly is changing fuel grades and brands. Don't cheap out all the time and get Bob's brew fuel, either.

reginhild

I live at 7500 ft altitude and have been getting 13-14 mpg around town with my 2008 FX4 Crew Cab with stock tires/wheels and no lift (Stop and go driving and very hilly). I added AEF CAI and Magnaflow Catback but havn't had tuned yet.

Lots of variables in MPG - note my altitude and the hilly city driving. For others the lift kit and bigger tires/wheels make a difference as well.

squirrelyyy

I have a 07 Lariat Screw b/4 upgrading my tires to 33's I was averaging that 13-14 around town on highway getting in the neighborhood of 18-20 since the new tires between 12-13 /16-18 oh by the way unless you have a tuner and can change the pcm I believe these trucks are setup to run on 87% oct the dealer told me if you run anything higher you can burn out the valves

chucke311

Cool thanks people. Its weird about the octane cause just looking at some other threads on here I've seen others saying the same thing about lower is better. When I first got the truck I was getting about 13.5 but since I've seen it get as low as 10.9. And I always run Premium. (even run some octane boost to see if it would help) So Ill try some lower octane(save some money). And just a added note, the truck is 4wheel drive and stock tires.

SinCityFX4

Sounds about close to the norm. I average 10-12 city driving, but mine is a little modded and a little on the agressive side driving. Just a little