Is there any noticeably difference in mpg betweeen the two? Both freeway and city. CAn you just post your mpg numbers if you have a 4.6? and a 5.4? thanks a lot -Mark

 

I have a 2000 4x4 with the 5.4 and I get around 13city/16highway.

Just came back from New Mexico and I averaged 16....

Hope this helps...

 

With my 1999 F150 and 4.6 engine, I will get 19 - 20 mpg on the highway in warm (summer) weather. In winter, that will drop to 17-18 mpg. City driveing will give me 14 - 15 in summer and 12 - 13 in winter. Fortunately, most of my driving is done on the highway.

 

If I'm very nice, I can average 17 mpg with my 5.4L. However, I do have a personal worst of 178 miles to the tank (7.12 mpg) .

-Flea

 

FWIW, I have just over 500 miles on my 4x4 5.4L. Tank #1 was 12.5, tank #2 was 13. I am really hoping this will get better.

 

Flea, what happened to get 7mpg. I can only imagine.

With the 4.6 I would estimate I get 18-22 mpg highway and 16-18 mpg city. The winter does bring the figures to the lower. I am lucky if I get a chance to drive my truck at all during any given week. (I drive a '99 E-250 for work, 5.4, nice van.) When I do get a chance to take a ride it tends to be with a heavy foot. That assures that the figures will be lower.

Since I brought up the E-250, I will let you know that that thing gets something like 11-14mpg. I am happy if I get 12 or 13 mpg. What a difference from the F150. The van is loaded up with tools and stuff. The engine is setup different from the 5.4 in the F150.

Tom

 

99 Expedition EB 4X4 5.4 averages about 14.7 to 15.5. Have seen a couple of 17's on trips, but you have to drive it like there is an eggshell mounted on the throttle. This one has the 3.73, so its geared a bit lower than the newer ones.

 

I've owned a '99 F-150 SCab 4x4 with 4.6, auto, 3.55 gears, 265/75/16 tires, and a '00 F-150 SCab 4x4 with 5.4, auto, 3.55 gears, 265/70/17 tires, and a '01 F-150 SCab with 5.4, auto, 3.55 gears, 265/70/17 tires. I've put about 30,000 miles on each truck and overall I average better gas milage with the 5.4, about 15-16 mpg. If I drove a regular cab 4x2, I would probably do better with the 4.6.

 

I HAVE A 4.6 REG. CAB IT'S LOWERED ,BUT STOCK RIMS AND TIRES( MORE AERODYNAMIC?) AND THE BEST I HAVE EVER GOT WAS 17MPG. GRANTED I AVG. 85 MPH ON A TRIP TO SACRAMENTO FROM S.D. I USAULLY AVG. 16MPG. I TALKED TO MY FATHER LAST WEEK AND IN HIS NEW CHEVY EXT. CAB HE SAYS HE AVG.19-20!HOW CAN THAT BE?

 

i get a consistent 14.6 mpg with my '98 xlt 4x4 auto 5.4liter. 3.55 gears and off road pak with 17" tires.

 

My 5.4 was a sucky 10mpg until after broken in. It has been consistently 14/17mpg since. The mods made up for the 4.10s.

 

I only get 12 mpg average.And the truck is gutless. How in the heck do you guys get 20 mpg???? The best I have ever gotten is 14 on the highway doing about 70mph. I have had it to the dealer and they say nothing is wrong. At least gas prices are low now

 

My F250LD 4x4 gets exactly 19.0mpg. I drive exclusively highway miles, up a mountain and back down, 70 miles/day, 5 days/week. I have the 4.6L and the 5-speed with 3.73 gears at both ends. In overdrive at 60mph the engine's turning 1900rpms.
I use 89 octane fuel, and have the 30 gallon tank.
I have calculated the mileage based on the last 6 tankfuls of fuel. I think the 5-speed has really helped economy, allowing me to keep the engine's rpm exactly where I want them at all times.

 

John, let me clarify that for you.

You get 9.5 mpg going up the mountain and 28.5 coming down.

 

I've had three Ford F150's, all 4x4, Supercabs, shortboxes. All had the same cab height fiberglass topper. All 4.6 V-8s. 3.55 gears.

The l997 averaged 15.7 mpg over 38,000. The 1998 averaged 14.8 mpg. My 2000 is averaging 15.3 mpg. I record every fill and this included all driving, including acouple of trips per year to Canada with a boat behind. I'm getting about 17 on the highway and 13 in town. If anyone ever finds a Cheve 4 wheel that gets over 18 mpg they better buy it!! I have run many times with Cheve pickups with both towing boats and it doesn't make any difference which V-8 they have the mileage is always alittle better on the Ford. From what I've heard the 5.4 truck uses about 2 more gal. per mile that the 4.6.