when it was bone stock I was getting 13-14..... now I'm getting 10-11 due to all the cool stuff :-X06

Is this with the economy or performance tune? Stock or modded engine? And most importantly does it require premium fuel or regular?

I see you're getting 18 mpg highway and 12 mpg city with the K&N and tuner. I have a 08 SD with the 5.4 engine with a Flowmaster exhaust and K&N cold air intake. I get 13 city and 19 highway. I have thought of getting the tuner but have heard conflicting results. Some say it improves HP and some say it hasn't improved HP and mopg got worse. Do you recommend getting the tuner?

Our unit is a 2009 F-250, SD, XL, 4X4, 5.4, automatic, 4.30 gears with factory limited slip, CC, LB with stock tires and rims.

It came from the factory with 3.73 LS gears and we changed them out for the 4.30's.

With the 3.73's we got around 15 MPG empty interstate driving, and that was being very careful with the right foot.

After the change to the 4.30's it dropped to around 14 MPG on the interstate bein' careful.

Towing our 8500 lb. fifth wheel we got about 7-8 MPG with the original 3.73's. Towing the 5ver with the 4.30's we get between 8.5-9.5 MPG. I suspect our towing mileage will be a little better than the 8.5-9.5 in some situations but we haven't pulled it that much since we went to the 4.30's.

One thing is for sure, the 4.30's really put some towing guts into the little gasser. She'll hold her own. It's now a joy to tow the 5ver, no more shifting at every overpass or slight hill.

I really wish i could afford to put 4.30s in my truck. Driving stock with 3.73s is bad, 35s is just awful...

acf6, we bought this unit at a low enough price we were able to justify spending the money for the gears. Otherwise we wouldn't have been able to swing it.

A word of advise though, if you ever get around to regearing your truck and you're running tall tires you might want to look at going with the 4.56/1 ratio.

Our unit has the basic standard tires and they're short enough that the 4.30's are fine. Any taller though, and the 4.56 would be the way to go.

I just gotta say I love all of the F250 5.4L drivers who are getting 18-19 MPG highway, but offer no other explanation. :-blah

It seems most of us average around 10-12 city 13-14 highway, which is about what I get. Sometimes more, sometimes less.

I wish I had the magic solution-that you all have to get even 16 highway, but personally wonder if that solution is just typing on the keyboard..

Through us a bone here and at least tell us what you're using to achieve such high MPG on the same truck we all drive, more or less.

I can get 15-16 highway easily, I just drive 68mph or so. In town is where mpg sucks


Date - Miles - Gallons - MPG - Price

12/16/12 / 96.0 /5.50/ 17.5 /3.699 (100% highway trip coming home from vermont) filled up in vermont when fuel spilled out and filled up at home when fuel spilled out
8/25/12 /243.0 /16.43/ 14.8 /3.999 (round trip going to and from vermont with a snowmobile in my truck)
7/8/12 /303.0 /19.65/ 15.4 /3.739 (trip to new jersey)
12/31/11 /103.0 /5.62/ 18.3 /3.479 (same trip as 17.5 mpg one)
8/21/11 /340.0 /27.38/ 12.4 /3.899 (this was around town alot)

etc etc...

2005 F250 4x4, 5.4 auto, manual hubs & transfer case. Extended Cab short box. 3.73 gears, LT275/70R18 tires (60PSI), regular height canopy and a slim boat rack. empty truck- just me. blended mpg (25% in town- 50KPH, 75% highway-80KPH) using cruise control and a light pedal. 82,000km, all stock.
9.8, at best.
Towing (@6000lb) about 8...
I'm hoping the cat is clogged, or??
It's getting a tune, a complete new exhaust and a good look over. It can't get any worse in my opinion.

2002 F350 4x4, 5.4l 2v auto trans, manual hubs & transfer case SRW regular cab 8ft bed
265/75r16 E rated Firestone TransForce AT tires - 55psi front - 45 psi rear
Tailgate removed

Lat two fill ups - mix of 35% around town - 65% hwy
Unloaded

14.2 mpg (rear tires were at 36) - 14.4mpg (rear tires at 45)

I was running techron during both of those 3/4 tankfuls so I hope to see some mpg increase with this next fill after going to mobil 1 full synthetic engine oil and stopping the techron regimen. Using 89 octane "plus" gas from sunoco.

I rarely accelerate past 2500RPM, mostly keep it at 2000rpm or very close, I cruise at 60-65mph.

Up around 72-75+ the tires start sounding loud and I really dont need to drive that fast EVER in a pickup truck for any reason. Don' see the point, I sold my audi.

If I had to guess I would say I am probably getting 10-11 city and 16-18 highway wi the f350.

I used to get 10-11 mpg city/highway in the 1988 bronco small v8, and 4mpg on the beach in 4x4 lol Gas was also $1.15 in the late 1990's in NY !!!!!!

JC

hello Can somebody reply chris if they can see this message

I see it :-X22

Last four Fill ups:

This is all mixed 60% hwy, 35% city, 5% sand

14.33 mpg

14.26 mpg

13.47 mpg (I was at idle with the air conditioner on for over three hours with the girl!)

14.88 mpg (480 miles total mixed to calculate this one, 325 in one day was 60% hwy - 15% windy & HILLY back roads in connecticut 25% heavy traffic WITH additional 500lb of Cargo (designer furniture in bed)

I haven't been above 70 mph, 4:10 gears, most driving I am below 2000 rpm when I accelerate and I cruise at 62-65 mostly at 2000 rpm exactly pegged. New Firestone Transforce At's have about 1,000 miles on them 265/75r16 (E rated)
55 PSI front 56-60 rear

Regular gas only, 4:10 gears, no additives other than what is in Sunoco and Shell reg.
Mobil 1 synthetic 5w20 in the crankcase.
Fl820S Motorcraft filter

Has consumed just under 1/2 a quart of oil over 3,500 miles on the latest oil change. There are no leaks.

I am considering using Conventional or "DINO" oil (Mobil super 5000) on my next oil change based on recommendations for BOBISTHEOILGUY forums.

Any thoughts?

JC

Last two fill ups with 87 octane Both 70% hwy 30% city, 50% of this time I had almost a full ton of rocks/dirt fill in the bed: 60psi rear 56 psi front tire pressure:



15.45 MPG (best yet)

15.08 MPG


Again, I am attributing this to not running techron additive in about 7 tanks full, and I removed the oil that I had in when I ran a 40 gallon techron treatment (two bottles that treat 20 gal each) in my 38 gallon tank twice successively to "clean out stuff". The oil I am running now is pennzoil yellow bottle 5w20. It runs nice and quiet and it seems to have helped fuel economy 5-7% or so. I am surprised that the mileage got better with a load...... Can't grasp this.

JC

I now realize, that prior to my purchasing the vehicle the gas tank was replaced! So I am a little more at ease as far as the tank/pump/filter being dirty, not worried as it obvioulsy hasn't gone 120xxx miles.

Last two fill ups for me: 11.8 and 11.4

damn you 35's :D