I talk to a guy at the gas station with a I think a 2000 f-250 2wd reg. cab 6 spd, 4.10 gears and he said he is lucky to see 14 mpg on the highway. I have a 2008 f-250 CC 4X4 auto w/ 3.73 and I have seen 18 mpg on the highway driving 60-65 mph.

 

Comparisons between the 2-valve and 3-valve engines is complicated by the fact that the 2005+ chassis is so much heavier. In theory since the 3rd valve is on the input side and there is supposed to be better fuel/air mixing with the extra intake valve, maybe the 3-valver gets some better mileage. But you generally won't see it on account of all the extra weight.

Then too, what do I know. I thought you could no longer get a 2005+ with a 3.73 because they were all 4.10's now.....

 

I wish they all came with 4.10's.

 

ditto on the 4:10 I love the snappyness of my friends. over my 3:73 but he also likes my 3v eng and tranny more.

 

18 MPG?? I have a 2003 250, 4x4, four door short bed with the 5.4 and I am LUCKY to see 12 MPG. I just got back from a 1000 mile trip all highyway and got 13 MPG on one tank and the cruise set on 65. Should I be worried?

 

I usually get 13-15mpg, for my normal driving area & style. I keep a spreadsheet on this and my lifetime average is 13.99mpg with a record low of 10.3 and a record high of 17.6.

Recently I got 16.5mpg between Asheboro, NC and Myrtle Beach, SC. Then I got 11.5 all week driving around town. Then 16.0mpg on the reverse trip.

 

I think a lot of the difference in mileage has to do with the speed you drive. Most people will not travel that slow on a freeway with 65+ mph speed limits.

Now, somebody is bound to claim that you can't possibly get that good mileage and/or can't do basic math. I think you can do that well if you really have enough discipline to set cruise and let everybody pass you. At 64 mph I get 22 mpg with my 7.3L diesel. That's 22% better then your 5.4L which is in the correct ball park for what a diesel should do. 18 mpg with a 5.4L seems doable to me.

However, 14 - 16 mpg is probably more typical of what a 5.4L owner will report. My own fuel economy will drop to 19 mpg at 68 mph which again is 20 some percent better. It all seems to add up compared to my own experience.

 

Further complicating the comparison is the transmission, you get an extra gear with the 3V engine.

Steady hiway cruising unloaded I can get up to 18 MPG, but normally I get around 15 MPG per tank.

 

Is there a difference in the final drive ratio in top gear?

 

In my mind, you are doing quite well in MPG's. My '88 F-150 is getting about 13-14 combined and 16-17 hwy. Your trucks are much heavier and twice as capable as mine and my mpg's are no better.

For those of us concerned about axle ratio's, I've seen a ton of '09 SD's with the 6.4L on the lots running 3.55's and smaller diameter tires.

Tim

 

Not really. The 4R100 and 5R110 both have the same last two ratios. (1:1 and .71:1) The variable will be the tire diameter. For instance a stock tire for a 20" rim will be larger in diameter than a stock tire for a 16" or 17" rim. Overall weight, terrain, driving style, fuel type, method or caluculation and etc all play a role in mpg.

 

The most ive seen in my 2006 harley davidson f150 is 18.6, but it wasnt easy. Lots and lots of careful hwy driving, with the use of neutral on downhill slopes when necessary. But hey, 18.6 aint bad for AWD/4x4 w/ 22 inch wheels

 

I haven't had my 2010 F-250 5.4 on many highway trips but I finally broke the 13MPG mark around town. Of course I drive it like an old lady to get that mileage.

 

I believe it's the much maligned VCT that's responsible for the fuel economy improvement over the 2V engines. I was able to get 20 MPG in my '07 5.4L F150, so 16-17 in a Super Duty seems reasonable to me. Of course driving style is by far the most important thing.

You couldn't get an SRW PSD truck with 3.73s after '08. But you can't compare gear ratios with an engine that makes nearly double the torque as the other. The 6.7L PSD is rated to tow 16,300 lbs with 3.31 gears. The 6.2L V8 needs 4.30s to have the same capacity.

 

13mpg in town is not half bad for a big ol 250 though