I currently have a 06 F150 with the 5.4 V8. I am looking at getting a new 09 F150 4x4. Before the new 09 came out I was going to get a Super Duty diesel but from talking with owners of the 6.4 I hear nothing but negatives about the mileage they get out of them. With the increase of the tow capacity now on the 09 I think it will work well for pulling my holiday trailer. But back to the original thread question....with the new 6 speed transmission in the 09 is anyone seeing better fuel mileage over the previous 4 speed transmission? Looking specifically for answers on the 5.4 with the 3.73 gears.

 

I have the 09 platinum with 5.4 and 3.73 gears. However, I haven't had it long enough to comment on mpg. I've been told to wait until at least 1500 miles before making any conclusions on performance or mileage.

That said, what are you hoping for? I'd think the 09, at best, will be 1-2 mpg better than a comparable geared 04-08. Also, you realize the 3.73 is going to be 1-3 mpg worse than Ford's numbers, which are based on the 3.15, right?

 

No, those numbers are accurate, mine has only hit the low MPG one time and that was towing a trailer. The sticker said 13 city 17 highway, mine has the 3.73s and I usually get 16 city and 19 highway.

 

I have 3.73 FX4 with 20s. I drive it pretty hard accelerating fairly hard most of the time and run 75-80 as well. In mixed city and highway, I'm getting 15-16. Pulling my boat (still going 75-80) gets 10.

Same mileage I was getting in my diesel but a lot nicer, quieter, etc!

 

This truck and my '07 both have/had the 3.73. My round trip to work is the same with this truck. Adding 285x65x18 E range tires could have taken away any mileage improvements I may have seen over my '07. Highway mileage running 75 is around 15. I had hoped it would be a little better. If I slow down to around 70, mileage increases.

 

If I get that I'll be pretty happy.

 

My numbers are according to the computer. I've never checked it by hand. The 36 gallon tank is awesome too! 500+ miles to a tank of gas is very nice.