If I really, REALLY baby it, I can get 12mpg on my daily commute. On a recent trip towing my toys and with a 10' cabover camper, I averaged 8.5mpg. It's not a gas sipper and wasn't designed to be. But, for the power it delivers, I'm satisfied with the mileage.

 

10.5 Empty, consistently. Towing the camper (11k) 7-8.5 depending on where we tow to.

 

Please read my thread "Modified Exhaust."

My truck is a 2000 2v V10.

Looks like taking it easy in town driving I am now getting about 11 mpg.

It likes about 60-65 on the "flat" HWY for best gas milage, which seems to be about 15.5 mpg empty.

Higher octane gives me about .5 mpg higher.

This is a stock motor, only modification is to the muffler/tailpipe.
Suspension is a 5 in. lift, 4.30 gears, and 37 in. tires.
Lot of weight and resistance to push.
Wish I could put the newer 6 speed auto transmission in this truck.

Motor design is, in my opinion, a mistake.
Should be a 4 in. bore by the 4.125 stroke!
3.625 bore is a mistake!
That is another topic for discussion!

Steve in Tucson

 

My '99 F250 SC LB w/ 3.73s gets 13-14 empty in mixed driving here in Phoenix. However, I drive it like it's a big heavy truck (slow and boring). When my wife drives it, she gets 11-12. The best I've gotten is 14.1 average on a tank.

 

Ah, but CapriMikeC, you all those fantastic 101 and 202 freeways to boost your MPG in the Phoenix metro valley !

Is your truck lifted? Lost milage there.
Does your truck have REALLY heavy tires and wheels? Lost milage there.

I do need to change my plugs. Not sure how many miles on them, but I have put 36K on them, so.............

I have driven in the Phoenix area, and I also get better milage there as well. Might have something to do with the altitude.

Steve in Tucson

 

Steve,

Even with only freeway driving such as Phoenix to Las Vegas, the truck only gets 14mpg. It is 2wd, not lifted, and stock size tires.

Elevation can affect mileage. I think the gas blends have a significant effect as well.

I bought the truck with 59K miles in 2005 and it now has 147K miles. I changed plugs around 114K miles. There was no change in mileage but the truck started and cold idled a little better.

 

I've had 3 V10 Excursion's all 4x4 with 3.73's

I get 8-10 mpg city 11-14 mpg highway 7-8 mpg towing my travel trailer. I also have a SCT3 tuner with basically a ***** to the wall performance tune.



my plate says it all!

 

2000 Excursion Limited, 2WD, stock wheels, Michelin tires, Amsoil 0W-30 synthetic, 3.73 gears, loaded w/six adults & tailgating gear.

Best Ever: 165 mile test, flat interstate - 15.7 MPG with E0, cruise set @ 75

With E10: Same 165 mile test route, load & cruise - 14.5 MPG

Normal mix of town/highway 11 - 13

Note: Above reflects changeover to synthetic which bumped prior average 1 - 1.5 MPG

 

I've been keeping track since Jan 2012.

Avg - 8.97

Last - 10.79

Best - 11.31

 

I was reading over on the v8 superduty. Does not sound like the v8 does much better than the v10.

 

Had the 5.4 V8 in the 06 F250 and got maybe 1-1.5 better. But that was an ext cab long bed and not a CC long bed dually like the 350. Plus the V10 just moves when you mash the skinny pedal.

 

Had my 2010 for a month now, it is dead stock with 50k miles. It has 4.10 gears & according to the build sheet it rolled off the line with 18" wheels. Apparently some fool thought it needed a set of the factory 20"s on it before I found it. Combined city/highway unloaded was getting 10 mpg. Bought a set of factory 17"s and Toyo ATIIs in 265/70/17, now I'm getting 11 mpg. Have a Flowmaster ex. & Airaid intake waiting to go on, probly wait 'til I get the SCT tuner & do it all at once. After I get the snow plow springs off the front & a B&W Companion hitch, it'll be time to sell the old diesel.

Oh yeah, my work truck is a 2012 F450 V10 auto with aerial lift (aka AT&T bucket truck). It weighs somewhere south of 12k lbs, gets 7 mpg, and the 4.88 gears make it move off the line. Driving this baby for the last 6 mos. is what convinced me I did NOT need to pay $7-8,000 more for a diesel in my new-to-me personal truck.

 

On 7-2-14 I posted about getting 14 MPG while delivering my HiLo camper then returning empty. Well yesterday I repeated this trip (of course in reverse order, going up empty then pulling it home).

Same exact roads, same gas source (93 octane), same outside temps/environment, same driving characteristics (grandpa), yada/yada/yada.

As I think I still have some engine stumbling I'm going back to 87 octane.

Anyways, this time I only got 11 MPG. Go figure.

 

2005 F350 LB CC V10 4.10 gears

Empty on the freeway ~9.5mpg
Mixed around town ~8.5mpg
Towing 5-8k ~6-7mpg (depends on how many hills we have to conquer)

Disclaimer: I'm not known to have a light foot.

I'd probably do better if I wasn't running a 4" lift with 35's but I will never know...

However the little 5.7L GMC half ton this replaced only got 11ish around town, 12-13 on the freeway and I don't even want to know towing. That was with just a TB crank lift/blocks and 285 tires but wimpy 3.43 gears...

I'm ok with the mileage compared to the price of a comparably equipped diesel and the on-going maintenance required.

Makes me smile every time I get behind the wheel.

 

I owned a 2001 F250 2v supercab. Always gave me 10 mpg. Thats why when the wife told me I could have a new to me truck I started looking at diesels. We drive 20010 6.7 for work and they have been in the shop CONSTANTLY. Cab off ever other trip in.
I finally settled on a 2009 King Ranch with the 3v. We just got back from Anehiem (dippy land) and besides the parking, She was a blast. speed limit between SLC and most of the way there is 80 now, so I did 90, with a bed cover I averaged 12.5 MPG at the pump not the computer. Don't have my new fifth wheel yet, but can't wait to double down to lake Powell with the new toy!!