18MPG around town on 03 5.4l

[Brent Harward]

Ya. Smoke is right. But I'm gonna pass on where it was blowing...

 

[BillAlex]

Took a day trip up to Flagstaff AZ, Elevation about 7,000 feet from Phoenix (elevation 1,200 feet) and huge up hill. Total round trip about 300 miles and I average 18.6 miles per gallon. I did run with the cruise control on most of the way. It is a Reman engine and I cleaned the injectors prior to the trip with Sea Foam. The first 500 miles of break in I averaged about 16 mile per gallon but a lot of start and stopping. Mine is a Two wheel Drive only. Really impressed with the new Reman Engine and the performance. I do use Premium Gas.

 

[Don Hall]

2004 XLS 4.6 2WD owned since new. Never paid attention to MPG as XP annual mileage was about 1200. Now, with fuel gage problem, I'm using trip odometer as
the determining factor for fuel. Last reading was 10.1 MPG - not an average as the XP is only driven in town.

 

[CertusExpo]

Yes please!

I'm lucky if I get 12.1 on the highway keeping her at 68/72MPH!!

Then again, she's running 33" muds and has about 500lbs of gear from the 2nd row back but still.

 

[1955moose]

Larger tires than stock will affect mileage. 11 city is the sticker norm on my 2000 5.4 4x4. I get 10, and that's with short freeway trips back and forth to work. Best freeway mileage was about 16mpg, taking a 120 mile round trip. The same SUV as mine but 2 wheel is rated at 13. The 2 wheel 4.6 version of a 2000 is rated at 14-15 city. I guess if our op has a 4.6, and is real easy, and it's running on the leaner side of the fuel curve, then it's possible. He is one of the lucky ones. The new 3.5 Expedition is right around 18-20. He did it it for 1/4 the price!

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[Prince_Polaris]

Guys our op hadn't stated whether 2 or 4 wheel drive. If 4 wheel drive, I doubt it, best is usually 12 city, 16 highway. 2 wheel will bump about 2 mpg avg. So 13 on a normal running no codes no rich motor. If he's got the smaller 4.6 two wheel drive and drives like your 80 year old granny, yeah he might be able to squeak out 17-18mpg. But he's not having any fun doing it.

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Is the weight of a 4WD system enough to hurt your MPG, or do you just mean that having A4WD on will increase the MPG?

 

[1955moose]

Both. Even in Awd, the drag from the front components robs fuel efficiency. The extra weight of the differential, the axles, all the extra parts, fluid weight, etc .Same goes for accessories like AC. Ac compressors have a lot of drag. Type of tires can make a difference, along with tire pressure, even wheel alignment thats off, can Rob mileage. If the toe setting or camber is out of spec, the front tires struggle to roll down the highway. It's like our legs and feet, trying to walk down the street with a twisted worn shoe, or a knee, or ankle that's not in alignment with your hip and back. We get there, but it's a struggle. Same thing for your Suv. If fuel trim is too rich, like a vacuum leak, or misreading 02 sensor, and the computer compensates for it, fuel mileage drops accordingly.

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[Prince_Polaris]

Both. Even in Awd, the drag from the front components robs fuel efficiency. The extra weight of the differential, the axles, all the extra parts, fluid weight, etc .Same goes for accessories like AC. Ac compressors have a lot of drag. Type of tires can make a difference, along with tire pressure, even wheel alignment thats off, can Rob mileage. If the toe setting or camber is out of spec, the front tires struggle to roll down the highway. It's like our legs and feet, trying to walk down the street with a twisted worn shoe, or a knee, or ankle that's not in alignment with your hip and back. We get there, but it's a struggle. Same thing for your Suv. If fuel trim is too rich, like a vacuum leak, or misreading 02 sensor, and the computer compensates for it, fuel mileage drops accordingly.

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I've been wondering about my poor suspension, I looked at my car in a resturaunt window once and it looked like my back wheels had gotten touched by the camber gremlin! Like, it's hard to describe, but in the reflection it looked like the front wheels were vertical, like | | and then the back wheels... / \

But, back when the mechanic checked on that grinding noise (because I thought it was the suspension) he never told me there was anything wrong, so perhaps that's just how it be. Oh, and either I've gotten used to it or it's actually gone, but I don't hear that grinding much anymore!

 

[Jdcline54]

Guys our op hadn't stated whether 2 or 4 wheel drive. If 4 wheel drive, I doubt it, best is usually 12 city, 16 highway. 2 wheel will bump about 2 mpg avg. So 13 on a normal running no codes no rich motor. If he's got the smaller 4.6 two wheel drive and drives like your 80 year old granny, yeah he might be able to squeak out 17-18mpg. But he's not having any fun doing it.

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Its 4x4. I swear I'm not making it up or exaggerating. I've gone through about 3 more tanks since my original post and still averaging 15.9 ish.. I was the sole driver for the first little bit, but I have gone back to sharing it with my 16 year old...
Optimistically, I am attributing the couple of lost MPGs to 2 things.
1. Teenager driving...
2. It's been quite cold here the last month, and my expy spend a lot of time idling in the driveway before I head to the college, and about 15 more minutes of idling when I get there because I sit there and have a smoke...

The only detail I left out, is that when I took that picture I had just driven 100 miles on the freeway. 50-60 miles of that was mountain driving on US-6 and the remainder on I-15 from Spanish Fork, to SLC, ut.
But I didn't create the post until a week later.

YOU can't believe everything you read, but I promise, you can believe what I've written.!

Edit: I should also note I live in a small town... Speed limits around 30-35...
2 miles from my house to just about anywhere I go... So not a whole lot of "fast and furious" driving...

 

[CertusExpo]

I've been wondering about my poor suspension, I looked at my car in a resturaunt window once and it looked like my back wheels had gotten touched by the camber gremlin! Like, it's hard to describe, but in the reflection it looked like the front wheels were vertical, like | | and then the back wheels... / \

Mine were the same with my IRS. I bought the Rear Camber Kit to take care of that for Bonnie.

Amazon Link although I got a better deal from ultrarev.com

 

[Kryo-Genik]

My bone stock 03 EB shows like 9 and change mpg. It's weird as my lightning with a fully built motor and shit gets similar mpg. So I'm wondering if something is wrong with my EB expy as I figured mpg would be better than my Lightning

 

[1955moose]

03 Expedition mileage sticker for the 4 wheel drive versions are 12 city, 16 highway. The smaller 4.6 gets 17 highway, city same. If yours is 2 wheel drive the 4.6 jumps to 13 and 18. 9 and change is 3 mpg down. You might want to run, or have someone run fuel trim readings and if you haven't done it, pump up tires to proper spec, do a full tune up on engine.

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[johnboneske]

I get 11.9 city, 12.8 combo and 15.2 highway on average with my 2003 5.4 4x4 with 3.73 gears. I typically run around 72 in a 65 MPH zone, 74 to 76 in a 70 zone. I can't imagine getting 16 or better, would be awesome! Hell, my wife's 2006 2wd Trailblazer EXT 4.2 only gets about 18.2 on the highway. But then again i don't drive under 70 on the interstate.

 

[1955moose]

John your as close to sticker as anybody. If your anywhere near their sticker readings your doing ok. Your almost spot on. A little less speed and you'd be above sticker.

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